Stephanie is known for her perky personality. She was a blabbermouth in the earlier seasons, but got over that eventually, though her younger sister Michelle received that trait as well (but she grew out of it, also, at an earlier age than Stephanie). Stephanie is often defiant of her sister D.J. in the earlier seasons, but they eventually become much closer and bicker less as the series progresses, though her nosy habit of reading D.J.'s diary never faded, though her snooping on D.J.'s phone calls was gone by then. Stephanie is the most excitable of the girls—a trait she inherited from her mother, and the most talkative—a trait from her father. She often struggles with being the middle child and wanting attention (as seen in season 2's "Middle Age Crazy").
Still, she is quite well-behaved and very hard on herself whenever she did something wrong. For example, in season 3's "Honey, I Broke the House", after accidentally crashing Joey's car into the kitchen, she considers running away from home, and after being punished, is still hard on herself that she hides under the covers of her bed. Danny assures her that there's always the chance of building a new wall, or even buying a new car, but there's only one Stephanie Judith Tanner that can never, ever be replaced.
Although often noble and trustworthy, Stephanie has her weaknesses, which include being able to be swayed by her peers into dangerous situations, and prying. Like D.J., Stephanie is a good student. Her favorite color is pink. Stephanie is very athletic, as she also loves to dance and she performs ballet very well. Like D.J. and eventually Michelle, Stephanie is a member of the "Honey Bees" (an organization similar to Girl Scouts) in the first few seasons. Stephanie shares a room with D.J. until season five, when D.J. moves into Michelle's room and Michelle moves in with Stephanie.
She has a teddy bear named Mr. Bear, which she is very attached to, as Pam gave him to her when she and Danny brought Michelle home from the hospital. Mr. Bear wears a detective coat and a dark hat, and has a scar under one of his eyes. After season seven, Mr. Bear no longer makes an appearance, but he is mentioned in the season seven episode "The Apartment"; however, seeing as Danny wanted the stuffed animals raked up as well as Michelle's "Hobby Day" leaves, it seems that she did not completely get rid of him. As she mentions several times throughout the series, but is only heard twice (season two's "Goodbye Mr. Bear" and season five's "Oh Where, Oh Where Has My Little Girl Gone?"), "Mr. Bear is not a toy. He's a member of the family."
Throughout the series, Stephanie has gone through many tough issues (possibly more than the other Tanner girls), such as smoking (in "Fast Friends"), "make-out parties" ("Making Out is Hard to Do"), joy riding ("Stephanie's Wild Ride"), witnessing child abuse (of a friend in "Silence is Not Golden"), as well as the death of her mother when she was only five years old (and, as an adult, not being able to have children).
She goes to a different school from D.J. when she hits junior high, because of zoning problems related to the change from junior highs (grades 7 & 8 or 7–9) to middle schools (where 6th graders are no longer elementary school). This change was common in the early 1990s across the United States, which is when it takes place.
Stephanie enjoys her father-daughter time when she is little. She has a stage where she only wants to be with Danny, and never wants him to leave when she is young. Danny is a typical over-protective dad when she starts dating. However, in the season four episode Happy New Year, when Stephanie kissed Rusty, Danny did not seem to mind one bit (even though he only showed surprise and amusement on his part).
Uncle Jesse is a major role model of hers when she is little. Jesse thinks that she is very cute, and has also taught her how to ride a two-wheeler. Stephanie gets Jesse to do a lot of things for her, as displayed below:
Stephanie: "Uncle Jesse, let's play ballerina."
Jesse: "Uncle Jesse doesn't want to play ballerina."
Stephanie: "Yes he does."
Jesse: "No he doesn't."
Stephanie: "Yes he does."
Jesse: "No he doesn't!"
Stephanie: [pretending to cry] "Yes he does."
Jesse: [reluctantly] "How do you play ballerina?
Stephanie later forms a band with Kimmy and Gia, making Jesse proud, but also making family differences emerge when Jesse proves to be an overbearing band manager.
Stephanie, perhaps, has the best adult-to-kid relationship with "Uncle" Joey. Joey helps her out quite frequently when she is younger. However, as Stephanie grows older they do not interact as much. In "Slumber Party" (see below), she runs out of the Honeybee mother/daughter sleepover when he wears high heels, jump ropes, and plays with Barbies right in front of her eyes. Later, when she returns to the sleepover with D.J. (also below), she apologizes for running out and realizes he did all those things just for her.
D.J. is Stephanie's older sister, and is her role model (in the earlier years). As mentioned in "Joey's Place", she believed that D.J. was born so that she would have someone to play with—and even a friend to have when she started kindergarten. She was afraid that she would not make any friends on her first day, despite D.J telling her that she did not make any friends on her first day ("The First Day of School")—when Stephanie mentions Kimmy, D.J. said that while she and Kimmy had been friends/classmates from kindergarten through 4th grade, they did not talk to each other for six months. She ends the heart-to-heart by telling Stephanie that she's already made one friend, and that's her. They then head back to their respective classrooms. Also in "Joey's Place", D.J. mentioned that before Stephanie was born, her Bananarama poster did not have to be accompanied by Stephanie's Rainbow Brite poster, as it was at the time of the episode.
In "Back to School Blues", when D.J. starts junior high, Stephanie is afraid that she would not have her big sister to stick up for her anymore, but D.J. tells her that she did not have a big sister to stick up for her and she did just fine and says Stephanie will also fare the same fate. Also around this time, D.J. always taught her to learn from her mistakes and not always mope around all the time when things do not go her way—a lesson D.J. herself learned from "Sisterly Love" (despite the fact she was shown moping around for a while), and Stephanie subsequently picked up on in "The Seven-Month Itch (Part 1)" after fog canceled the family's Disneyland trip.
Stephanie is very curious about D.J.'s social life and listens in on her phone calls, reads her diaries and even attempts to find them, which (as described by D.J. in the season 3 episode "Bye, Bye Birdie"), contains her "hot stories"; and even once, D.J. even said that she had a journal, and not even Stephanie knew that D.J.'s "journals" and diaries were one and the same). D.J. promised to tell Stephanie about her fascinating life under one condition: the diaries/"journals" must be kept under her lock and key at all times.
Stephanie and Michelle sometimes get into D.J.'s business together; they were shown once reading her diaries ("Be True to Your Preschool"). She also borrows D.J.'s clothes many times while D.J. is taking showers and other times when she is not in the room, though Michelle joined in on this only once ("Support Your Local Parents").
Another aspect of Stephanie getting into D.J.'s business was in "The Prying Game" when Stephanie thought Steve was seeing someone else. She and Kimmy break into Steve's apartment, causing D.J. to go ballistic over this and ask Stephanie to leave. When D.J. gets home, Stephanie then tries to offer a bowl of popcorn to her sister as a truce, but she refuses, leaving Stephanie to warn D.J. that her words would come back to haunt her and even bite her, and angrily remark that maybe this time she messed up, but someday D.J. may need her, but she won't be around because D.J. wants her out of her life forever. D.J., realizing her words would indeed come back to haunt her and bite her, gets her sister back into the room and they have a talk about it.
They get along better in later seasons, and still have great concern for each other, especially after Stephanie's first joyride and D.J.'s threats to make her stop from going a second time ("Stephanie's Wild Ride"); that night, despite Stephanie not wanting to talk about it, D.J. decides they still should, as she thinks it still never dawned on her former roommate that she could get hurt, and she does not want the first thing on her mind when she wakes up the next morning to be "How can I make Steph miserable today?", to which Stephanie mentions such, and D.J. calls the remark "real bright" and says that Stephanie is losing it with the rebellious attitude, leading a still-rebellious Stephanie to say that D.J. doesn't understand, thus subsequently leading her former roommate to counter and tell her that it is she who doesn't understand. However, by stopping her from going on a second joyride, D.J. was not making Stephanie miserable as she thought; she did it for Stephanie's own good. In addition, when Stephanie remarks that D.J. hates to see her have fun, D.J. counters, saying that while she wants Stephanie to have fun, getting in a car and going joyriding with someone who drives dangerously—be it once or twice—is anything but fun.
In the first four seasons and part of the fifth, they share the same room, where D.J. has a mandatory rule where Stephanie must keep her own stuff on her own side of the room (similar to the rule she set in the series premiere, where Stephanie could not set foot on her side of the room, in addition to being prohibited from touching her stuff).
After her awful time with Joey at the mother/daughter Honeybee sleepover ("Slumber Party", see above)—where the other girls that do have mothers were happy and she was not (as she was the only one in her troop to not have a mother), and even wondering why she couldn't be happy like them—Stephanie tearfully explains that when D.J. was 8 years old, she got to attend one with their mother Pam; D.J. then explains that that does not mean that she doesn't miss her as much as Stephanie does. She also explains that when she attended the sleepover with Pam, she looked at those girls who did have a mother at that time, and felt the same way Stephanie does for those who didn't. When Stephanie asks how she can make the feeling go away, D.J. explains that it's hard to do that, but something that helps her cope with Pam's death is that she realizes that Stephanie is special in the same way she is, in that they have something that the other girls don't have; namely Danny, Joey, and Jesse, and, more importantly, each other. After their talk, they hug, and after Stephanie apologizes to Joey (see above), D.J. decides to accompany her on the return trip to the sleepover, where they decide to join in on the makeover fun with the other girls and their moms (one of the activities that caused Stephanie to storm out). In "A Pox in Our House", when Stephanie gets the chicken pox, D.J., who was invited to her first non-mother/daughter Honeybee sleepover since Pam's death, forgoes it to take care of her and the rest of the family. In "Sea Cruise", it is announced that D.J. is retiring as "Queen Bee" and from the Honeybees as a whole, so in true fashion, she passes the crown—or rather, antenna—onto Stephanie.
Michelle is Stephanie's younger sister, and is to Stephanie much like Stephanie is to D.J. after the room switch in "Take My Sister, Please". Michelle looks up to Stephanie, and Stephanie, even though she loves her, is annoyed by her in the same sense that D.J. was annoyed by Stephanie. Michelle is not as nosy as Stephanie was, however, as Stephanie is the one who encourages her to be nosy. Michelle usually accompanies Stephanie when they sneak into D.J.'s room to read her diary (which is one thing they enjoy doing without getting on each other's nerves, see above). In "Divorce Court" (season 3), she literally moves her bed out of her and D.J.'s room into Michelle's room, despite Danny telling both of them that Michelle was too young for a roommate at the time. From season five on, Michelle becomes Stephanie's new roommate and her pencil bed takes the place of Stephanie's old bed, while Stephanie gets D.J.'s old bed (and the desk and chair next to it). At first, Michelle was against the idea of being Stephanie's roommate (because she hated being called a "kindergarten baby" and a "little shrimp" by Stephanie and hated having her age of 4 ¾ misinterpreted and misjudged as 4 whole years old by both her sisters), but she accepted after Stephanie tempted and bribed her with a bag of cookies. Stephanie also alleviated the pain by inviting Michelle into a Big Girls' Club and taught her how to do its short, but simple, song and dance. While she initially had a problem with Michelle's Barney the Bear wall hanging, she slowly began to accept it, as she wanted to get rid of it, while Michelle, in return, wanted to get rid of Mr. Bear; this was part of a condition that to get into the Big Girls' Club, all the baby stuff had to go. The bears stayed, but since it was never mentioned, the two girls possibly got rid of the rest of their baby stuff. Like D.J., Stephanie's ways of caring for Michelle go beyond just safety. In "My Left and Right Foot" (season 8), when they both find Michelle soaking her shrink-wrapped feet in a bucket of ice water in an effort to shrink her feet, she and D.J. immediately get Michelle out of her frigid foot bath, keep a tight grip on her to stop her from getting back into the tub, and insist that if she continues, she will freeze her feet off or that bunions will grow and possibly cause permanent damage; though Stephanie was the one who said Michelle would freeze her feet off, while D.J. simply asked Michelle if she was "making a bunion Slurpee", but she did concur with Stephanie on Michelle's extreme possibility of freezing her feet off. In "Captain Video (Part 1)" (season 5), Stephanie retires from the Honeybees, and in true fashion, she passes the crown/antenna onto Michelle, and explains that the reason why Michelle's sash does not have badges is, like the Girl Scouts, they cannot simply get them; they have to earn them. After Papouli's death in "The Last Dance" (season 7), once Danny finishes having a heart-to-heart with a teary-eyed Michelle about the loss, Stephanie has one as well, reminding her younger sister that they have to be brave for Jesse as much as they can, and asking her to control her emotions and tears as much as she can, even though she understands how difficult it can be to do so after the loss of a loved one. After Jesse makes a brief visit, she hugs and praises her with a brief "Good job, kid" for indeed controlling her tears and emotions during the hard times the family would have to suffer as a result, similar to when D.J. comforted Stephanie regarding the loss of Pam (see "D.J."). Another trait is when Stephanie has friends over, Michelle constantly reminds her that they share a room, similar to how Stephanie did when she shared the same room with D.J.; an example of this was in "Driving Miss D.J." (season 5) where Stephanie had threatened to summon the "Hairy Scary Monster" by saying his name three times, if Michelle didn't leave Stephanie and her friend Rita alone. The plan was almost perfect as the "monster" turned out to be Joey, who slapped high-fives with Michelle over successfully scaring away Stephanie and Rita. He then has the two roommates call a truce, reminding Stephanie she can't scare Michelle away anymore, and Michelle that when Stephanie has friends over, she must go play elsewhere and give Stephanie some space. In "Misadventures in Babysitting" (also season 3), she gets her first chance to babysit Michelle by herself, while D.J. was out babysitting someone else. She offered Michelle a cookie not knowing Michelle had one, but all attempts failed; so she had to literally drag Michelle upstairs to bed. In "Comet's Excellent Adventure" (the season 8 premiere), when Stephanie saw Michelle at the street corner after Comet ran away while she was trying to walk him by herself, Michelle said that Comet ran after a "humongous wiener", but Stephanie wasn't buying what Michelle was selling. She went into a lecture about how her roommate "really messed up big time" by walking Comet by herself, and that walking a dog alone is a big responsibility, and didn't think Michelle was up to the task. In the opening teaser to "You Pet It, You Bought It", when Nicky and Alex were trying to wake Michelle up, she asked Stephanie how to wake up grumpy, and Stephanie barely opened her eyes and responded in a monotonous "Back off, or you're toast."
Stephanie is glad when Becky comes into her life, having a motherly figure to look up to. They get along well.
Nicky and Alex
Stephanie is very good with her twin cousins. She is not afraid to babysit—even in one episode when Nicky and Alex panic when she gives them the wrong pajamas. Once, when Kimmy was babysitting, she took over for Kimmy—for a price; as this was due to the fact that Kimmy didn't want to change the twins' diapers. Afterwards, since Stephanie was the one who did all the work, she was the one that earned all the money.
Kimmy is annoying to most everyone including Stephanie. They would often make fun of each other (as they sounded like a great comedy team). Stephanie is more tolerable of her in the last couple of seasons, though they both constantly shoot insults at one another. It's thought to be normal of them; Kimmy once asked sadly if Stephanie was mad at her when she had not insulted her back. When Stephanie said that she'd been called "Step-On-Me" at school, Kimmy said that the clue was the sign on the back of her jacket that contained said name.
Gia would become Stephanie's best friend when she grew older. In the beginning, Gia would often get Stephanie into trouble and has bad judgement (although she does grow out of it when they become friends). She is like Stephanie's Kimmy, since she brings excitement into her life.
Rusty is Cindy's trouble-making son. To get his mother out of his relationships, he pranked her boyfriend and his family. When the Tanners were the victims of his pranks, Stephanie, Michelle, and D.J. finally got him back. Once, Rusty teased Stephanie that he was going to kiss her on New Year's Eve, to drive her crazy. And it did. When he told her that he wouldn't actually kiss her, she surprised him and kissed him. After that, it was rumored that he liked her.
Stephanie likes Steve, but along with Danny, makes fun of how much he eats at their house.
Stephanie loves Comet. She was very enthusiastic about getting a dog, and grows up loving him, and even finds him to be a companion. When they first got Comet, she had suggested they name him "Mr. Dog" after Mr. Bear (the opening teaser in "Dr. Dare Rides Again"). In "Take My Sister, Please", after D.J. and Michelle reject her as a roommate, Comet "offers" her a place in his doghouse, but she rejects the offer as she finds it too small and uncomfortable for her.
- Danny Tanner – father
- Pamela Tanner – mother (deceased)
- D.J. Tanner – sister
- Michelle Tanner – sister
- Wendy Tanner – aunt
- Jesse Katsopolis – uncle
- Rebecca Donaldson-Katsopolis – aunt
- Nicky Katsopolis – cousin
- Alex Katsopolis – cousin
- Claire Tanner – grandmother
- Nick Katsopolis - grandfather
- Irene Katsopolis - grandmother
- Iorgos Katsopolis – great grandfather
- Gina Katsopolis – great grandmother
- Teri Tanner – step-mother
- Jackson Fuller – nephew
- Max Fuller – nephew
- Tommy Fuller, Jr. – nephew
- Tommy Fuller, Sr. – brother-in-law (deceased)
- How Rude!"
- "Hot dog!"
- "Pin a rose on your nose"
- "Nobody asked me"
- "Well, pin a rose on your nose."
- "Don't have a cow"
- "I love my life!"
- "Mr. Bear!"
- Favorite food: pizza
- Turn-offs: smoking and open-toed shoes
- Interests: dancing and baseball
- Her hair was curly in seasons 1–3, straight for most of seasons 4–8
- Favorite Book: Charlotte's Web
- Stephanie is right-handed (Joey once called her "Stephanie the right-hander" during a baseball game)
After Full House, Stephanie moved to London, England to become a DJ (comically, under the name of "DJ Tanner"). She later returned home to San Francisco.
- Main article: Fuller House
In Fuller House, Stephanie steps into a role similar to that which her Uncle Jesse played in Full House. She moves in with her recently widowed sibling in order to help raise the three children that D.J. is now left to raise as a single parent after her husband dies. Also like Jesse, music is also a big part of Stephanie's life.
After D.J. reluctantly agrees to let Max have a dog the Tanner-Fuller family brings Cosmo home in "The Not-So-Great Escape". Cosmo is the son of Comet Jr. Jr. and the grandson of the late Comet.
Stephanie reveals to D.J., in "Mad Max", that she is unable to have children. Stephanie found out that she was infertile while she was living in England. She did not say anything to D.J. about it because Tommy Fuller, Sr. had just died. In addition to being a DJ, she becomes the coach for the Van Atta Middle School dance team and occasionally sings.
Stephanie goes to London in the summer before coming back to San Francisco. In "Welcome Back", she kisses Jimmy Gibbler, Kimmy's younger brother. She begins dating him in season two.
She writes a song for her boyfriend which flops the First time it is released but soon becomes an Internet hit with a better video. It garners 400,000 views.
Stephanie is supposed to appear in an episode of Wake Up, USA, but because of being stuck in a cell set along with Jesse, Becky and Fernando, runs out of time.
- Full House Stephanie: These 33 books were written from the point of view of the Tanners' middle daughter, Stephanie Tanner. They take place with Stephanie in a different middle school, likely because of a slightly different redistricting plan compared to the one mentioned in season seven's Fast Friends. She has different best friends, Allie Taylor and Darcy Powell, as well. Though these are book creations, she has known Allie since kindergarten, and there are several places in the first five seasons of Full House where fans think an unnamed extra could be Allie. The first ten of these books overlap with seasons seven and eight of the TV series, though the school is not the only difference; there are a number of differences in the Tanners from the series. This series begins with Stephanie being pressured to join a clique called the Flamingos, by completing a series of dares. She almost does the last one, though she's not sure if she wants to, before D.J. catches her trying to steal Danny's phone card. Stephanie explains tearfully what was happening, and D.J. helps her to understand what the Flamingos were really up to: they wanted the phone card to use to call boyfriends. Stephanie and the Flamingos become fierce rivals, though not all books surround this rivalry or even show the Flamingos.
- Full House Sisters: These 14 books focus on Stephanie's friendship with younger sister Michelle and comical situations that occur between them. The sisters often alternate points of view in the story.
- D.J./Stephanie Flip-Over Book: This book features D.J. and Stephanie's opinions on different events in the book.