Nani is Lilo Pelekai's older sister and legal guardian. She carries the burden of supporting herself and her younger sister both financially and parentally. Naturally, she is usually very busy and under a great deal of stress. Her age is not made clear, but the fact that she was made her sister's guardian suggests that she is at least eighteen years old. She loves Lilo devotedly, but doesn't always understand her. Nani often serves as a gentle voice of reason and advice in the films and show - and occasionally, not so gentle. It was Nani, in the original film, who allowed Lilo to adopt Stitch from the pound, where he had been mistaken for a dog.
As a result of her stress, Nani is easily aggravated by Lilo and Stitch's antics, which often unfortunately interfere with her ability to find and hold a stable job. She frequently has to cope with and clean up after the various crises which involve Lilo, Stitch, Jumba, and Pleakley (who often tries to help around the house, with mixed results). Her busy life sometimes makes it difficult for her to maintain a normal relationship with David Kawena, a local surfer, who is Nani's friend in the original film and later love interest. She is renowned among her household for her bad cooking. Her worst fear is noted to be losing Lilo to social workers like Cobra Bubbles, whom she at first disliked but, after the events of the first film, comes to trust and respect.