Mertle Edmonds

Mertle Edmonds is Lilo's arch rival and a recurring character in the Lilo & Stitch franchise. She was voiced by Miranda Paige Walls in the original film, and by Liliana Mumy in all other appearances, starting in Stitch! The Movie.

Personality
Mertle is an incredibly spoiled yet beautiful little girl. She is the leader of a clique of girls who follow her every command. She has a strong disliking towards Lilo and refers to her as "Weirdlo" for most of the franchise. It was shown in the television series that her friends are not too fond of her bossy attitude. Mertle takes great pleasure in putting down, insulting, bullying, and making fun of Lilo.

Lilo & Stitch
Mertle is a young girl attending the local hula class alongside Lilo and three other girls: Elena, Teresa and Yuki, who act as her sidekicks. She gets into a fight with Lilo during one of their practices. After Lilo adopts a "dog" named Stitch, Lilo introduces her pet to Mertle, Elena, Teresa and Yuki. However, Mertle openly expresses her disliking toward the creature, calling it "the ugliest thing she has ever saw".

Lilo & Stitch 2: Stitch Has a Glitch
In the official sequel, Mertle serves as the main antagonist. She enters a hula competition against Lilo, which prompts the latter to practice hard, ignoring Stitch and disturbing their friendship.

Stitch! The Movie
Mertle is a minor character in the film, appearing back-and-fourth throughout the picture.

Lilo and Stitch: The Series
She became a recurring character in Lilo & Stitch: The Series. Throughout the series, it is established that she is from a relatively wealthy family and is a spoiled brat who lives with her mother. In one of the episodes, it is revealed that she keeps Gigi (Experiment 007) as a pet, but does not realize she is an experiment. She is associated with Hamsterviel. In the episode "Finder" she mistakes Dr. Hamsterviel for a gerbil and keeps him as a pet for a short time, then in "Shush" when her friends break up with her after Lilo wrongly thought she hated them she teams up with Dr. Hamsterviel, who apparently turns her into an android in order to catch all the other experiments in place of Gantu but was rescued by Lilo and Stitch, who took her to Jumba to de-rebot her. Lilo tries to be friends with Mertle in several episodes, but this usually just results in even more social rejection. She is rejected by her friends in "Tank" and teams up with Stitch to capture the experiment. They fail and are captured but manage to escape in Stitch's dune buggy while Gantu gets the experiment. She initially tries to tell her friends about it, but stops and becomes friends with them again.

Leroy and Stitch
In the final film, Hamsterviel plotted to rule the galaxy using an army of Stitch clones named Leroy. He orders Leroy to kidnap all 623 experiments, including Gigi. When Gigi was captured, Mertle was taken as well. At the final battle, Mertle ran in fear whilst Stitch and his cousins battled the Leroys. In the end, Mertle and Gigi joined Lilo and her ohana in a huge family picture.