Cookie Monster's Sister is the offspring of Cookie Monster's Pop and Mommy, and sister to Cookie Monster. She joined Cookie and their mother in singing "Me Gotta Be Blue".
The puppet was previously used as Cookie Monster's cousin, Cousin Monster.
Ad blocker interference detected!
Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers
Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.