Mouse (who is played by Jacinta Wawatai) is one of the youngest of the Mall Rats, but overwhelmingly articulate and sensible for her age. Salene found Mouse alone and scared in the city and takes her to the mall, they are followed by Mouse's brother, Charlie. At first it seems that the chidren cannot speak, but slowly they warm to their new friends and they begin to talk and evertually share their names. Mouse is devastated when her brother vanishes. Charlie's disappearance is assumed to be the work of the Technos but no evidence was ever found to support or deny the accusation.
When the power is switched back on, Mouse meets a new friend, Sammy, and brings him back to the mall to live, and they soon become best friends. They liked to experiment with the newly reintroduced electricity and blow things up, also playing tricks on the others living in the Mall, especially Jack, whose inventions seem to have a great effect on the children. Mouse and her new friend Sammy both love the newfound electricity and once almost set fire to the entire mall. They couldn't wait for City-Net to start, one of RAM's inventions, the first channel to come out on the computers.
Whilst the two always remain best friends, their relationship is strained significantly due to Sammy's addiction to Paradise and Mouse's fear of the program. Mouse's favourite game is the infamous "The Skunk In The Cup" routine, which, during one occasion, caused her injury when playing the game while jumping on her bed. Salene found her on the floor hurt having fallen off the bed. While she likes fun and games just as much as the next kid, she also demands responsibility and respect from those around her and is well aware of the complexity of the situations around her, even if she can't comprehend the details. In the fifth season, Mouse becomes aware of Salene's developing alcohol problem and attempts to help her tackle the addiction. Always eager to join in, Mouse frequently gets herself into scrapes, following other Mall Rats in the belief that she can help out - though, while occasions where she does are rare, there are some where she is just the right kid for the job.
When the city gets too dangerous, Mouse expresses an interest in living with the Eco tribe and attempts to run away to the countryside in the hopes of finding them. Her first attempt failed and she was returned to the Mall Rats by Mega. Despite the Mall Rats' insistence that she belonged with the tribe and was safe and loved, Mouse still feared the city and harboured a secret desire to leave. On her second attempt, Salene follows Mouse and then accompanies her to go live with the Eco tribe, where she participates in a ceremony to be accepted and admitted to the tribe.