Codename: Kids Next Door - Season 4 - Eps 18: Operation M.A.U.R.I.C.E.
An operate named Maurice is decommissioned from the Kids Next Door after he attains the age of 13. He has been working on a cure for chicken pox. The one who is saddened the most by his departure is Numbuh 5, so she suggests that they keep an eye on him so that the teenagers don't recruit him.
About Codename: Kids Next Door

Title: Codename: Kids Next Door
First Air Date: 2002-12-06
Last Air Date: 2007-11-23
Status: Ended
Rating: 8.2/10 (from 731 votes)
Language: EN
Seasons: 7
Total Episodes: 139
Network: Cartoon Network
Genres: Animation, Action & Adventure, Comedy, Sci-Fi & Fantasy, Kids, Family
Production Companies: Curious Pictures, Cartoon Network Studios
Synopsis
Taking numbers instead of names, five extraordinary 10-year-olds form a covert team called the Kids Next Door with one dedicated mission: to free all children from the tyrannical rule of adults.
Cast

Ben Diskin
Numbuh 1 / Numbuh 2 (voice)

Lauren Tom
Numbuh 3 (voice)

Dee Bradley Baker
Numbuh 4 (voice)

Cree Summer
Numbuh 5 (voice)