Never Forgetting Squeakers

Plot Summary
Six's pet mouse and best friend for life, Squeakers has passed away and Six doesn't realize that he's gone for good at 1st, but their mother tells her the truth that Squeakers is gone for good and has just stopped breathing but that makes it super hard for Six to understand that Squeakers is gone for good and never coming back even though Squeakers was Six's best friend for life, but she wants to have some alone time with him and the other monsters give him a funeral ceremony while burying him right outside in their backyard and Six spends her own time crying a bit and grieving, but they should find her a new pet mouse from the pet shop.

Trivia Notice
Three is a reverend named Reverend Three in this episode.

Transcript
Never Forgetting Squeakers transcript