When Marion finally gets the chance to babysit her little sister, she finds that the task is harder than she expected, especially when she gets called to the Critter Club to help with a stray cat and must bring Gabby along.

After Madeline Finn adopts a puppy, she learns about her local animal shelter and organizes donations and volunteers to improve the lives of the animals there.

Taking a turn caring for the class pet hamster, Marion is devastated when the hamster goes missing and she receives an anonymous letter in her locker with clues leading to a mysterious scavenger hunt.

"Ellie has always wanted to go to wedding, and her hopes finally come true when her cousin asks her to be a flower girl at her wedding. Then the Critter Club gets the cutest guest Ellie has ever seen: a little French bulldog. Ellie works hard to find a home for the puppy, but she's worried she won't be able to. Suddenly she has an idea that will guarantee that the puppy lives happily ever after!"--