She is the older sister and legal guardian of Lilo. She first appeared in Lilo & Stitch and has been portrayed in all media by Tia Carrere with the exception of the PlayStation video game in which she was voiced by Vanessa Marshall. Nani has been present for 43 episodes only out of 65 and also has been absent for 22 episodes out of the whole series making that 65 episodes.
Nani is Lilo's older sister, and was appointed Lilo's guardian after the deaths of their parents in a car accident. She is said to be 19 years old in the first film. As a result of having to support herself and Lilo she is often stressed and busy. Her business often interferes with her friendship with David, whom later serves as her love interest. She does care deeply for Lilo, and fears losing her to social workers like Cobra Bubbles. Nani is known for her inability to hold down a full-time job, due in part of the adventures of Lilo and Stitch. She is also noted for being a terrible cook.
In the TV series, Nani's main clothing is a sleeveless blue top, khaki tan pants, and blue opened toed sandals. In every appearance her tops are short enough to reveal her belly.
Nani appears in the film, having become Lilo's sole guardian after their parents' recent death. Nani is visited by a social worker named Cobra Bubbles who is concerned that Nani cannot adequately take care of Lilo. He is considering putting Lilo in foster care, but Nani refutes this by citing that she is the only family (A.K.A. "ohana") that Lilo has left. However, Nani will have to prove that she is capable of caring for Lilo in order to prevent Lilo from going to a foster home, a task that proves to be a difficult one.
After realizing that Lilo has no friends at hula school (Mertle Edmonds and the other girls bully her), Nani allows Lilo to get a pet from the pound. Lilo chooses Stitch, who, unknown to either girl, is actually an alien. Later, Nani is forced to take Lilo and Stitch with her as she tries to find a new job. Unfortunately, Stitch's attempts to evade capture by Jumba and Pleakley keep ruining her chances. Nani's friend David, having seen Nani, encourages Nani to take Lilo surfing with them to improve their mood. However, Jumba makes an attempt to capture Stitch from underwater. To everyone, it appears that Stitch had tried to drown Lilo. Mr. Bubbles sees the whole thing and tells Nani that he will come for Lilo in the morning.
While waiting for Mr. Bubbles the next morning, Nani is informed of a job offer by David. Nani orders Lilo to stay at home while she goes to apply. While she is gone, a fight between Stitch and Jumba results in the house being destroyed and Lilo calls Mr. Bubbles for help. Nani returns at the same time as Mr. Bubbles arrives and the two have a brief argument over Lilo's well-being. When Lilo is kidnapped by Gantu, Nani accompanies Stitch, who has revealed his alien origins, in Lilo's rescue. At the end, Nani and Lilo are appointed as Stitch's wardens by the Grand Councilwoman while Cobra Bubbles, who is revealed to be a former CIA agent, is enlisted to supervise the new family.
Taking place some time after the events of the first film, Nani has adjusted to life with an extended family, now living with both Stitch, Jumba, and Pleakley. Her regular occurrences include keeping the house in order, despite the color cast of characters that inhabit it, raising both Lilo and Stitch, working her job at the beach, and spending time with David, who she is said to have been dating for three weeks by the beginning of the film.
On an ordinary day, Nani is preparing "Family Night" at the Pelekai household, asking Jumba and Pleakley for assistance, though she faces denial on rather nonsensical accounts. Later that day, Nani is visited by Moses, Lilo's hula instructor, who reports a recent altercation between the latter and Mertle Edmonds. Nani invites Moses inside to talk over Lilo's behavior, but she is interrupted by a meddling Jumba and Pleakley, who disguises themselves as the Pelekai sisters' uncle and aunt, respectively, and try to convince Moses that Lilo's behavior was merely a misunderstanding. Nani is then approached by David, who makes an attempt to strike a date with the former, only to face rejection due to Amani's hectic schedule. Having enough of Jumba and Pleakley's attempts to help, Nani takes Moses and Lilo outside, where Lilo is given a warning: should her attitude remain low, she will be banned from an upcoming hula competition.
Over the course of the following days, preparation for the competition, as well as odd behavior with Stitch's programming (said to be a malfunction by Jumba that, if not rectified, will result in Stitch losing his life) begin to cause a rift in the relationship between Lilo and Stitch. When Nani comforts Lilo one night, asking why the competition is so important to her, the older sister learns Lilo's stress and desire to win the competition is a result of the sisters' deceased mother, who won the same competition when she was Lilo's age. Now with an understanding of Lilo's pain, Nani assures her younger sister that their mother would be proud of the former, just for being her. In turn, Lilo assures Nani that their mother would be proud of her efforts at parenting, moving the older sibling. Also occurring throughout the days is a side story with David who, because of Pleakley's poor advice, believes his relationship with Nani is dwindling and struggles to save it.
When Dr. Hämsterviel demands a ransom of Jumba's first 625 experiments, Nani contacts Mr. Bubbles for assistance while Lilo and Stitch set out to capture Experiment 221.
Nani is usually seen working a variety of jobs to support herself and Lilo. As always, she is concerned for Lilo's well-being, though she does allow Lilo to capture the rogue experiments. The episode "Retro" features Nani's middle school friends, who mistakenly believe that she is the Vice President of the company she works for. She sometimes helps with the experiment-hunting, such as in the episode "Phantasmo" where she saves Lilo and Stitch from a ghost-like experiment. She also rescued Lilo from being annihilated by Gantu in "Fibber", where she also briefly pretended to be Pleakley's fiancée.
Nani is seen after Lilo, Stitch, Jumba and Pleakley return from the Galactic Federation with awards for the successful extraction of the 625 experiments. Stitch, Jumba and Pleakley turn down their awards at first to stay on earth, so as not to break Lilo's heart. However, Lilo notices that they really do want their dream rewards and Nani convinces her that she's doing the right thing and showing aloha spirit by letting them go. Later on, after an evil clone of Stitch named Leroy arrived on earth to kidnap the experiments, he sneaks into the house and pretends to be Lilo when Nani almost notices him. At the end of the film, Nani is seen alongside David, Lilo, Jumba, Pleakley, Stitch, Mertle and all the experiments, taking an ohana picture.
Nani appears briefly in flashbacks in "Reunion with Lilo!", including a brief scene where she, Jumba, Pleakley and Stitch see Lilo off to college. Somewhere during this time period, she had a child or was about to have a child, which delayed Lilo when she planned to come back from college to visit Stitch, leading him to leave Earth.