A mouse named Wemberly, who worries about everything, finds that she has a whole list of things to worry about when she faces the first day of nursery school.

The Worrier visits Felix night after night, reminding him of what could go wrong the next day, until the night that a special birthday present changes everything.

Jessica, who worries about everything from her spelling homework to remembering to fill her dog's water dish, learns that fire safety begins with extinguishing her fears.

When Daddy Rabbit announces the lake is hard enough for skating, Bella worries about what could happen, but as she hesitantly tries, she finds her worries are all for naught.

As brother-and-sister dogs Digger and Daisy head out to the woods to camp, Digger worries about bears.

Piggie ruins a perfectly good day by telling Gerald the elephant that she is going, sending him into a panic.

Dinosaur worries about the first day of school, but with the help of a a reassuring classmate he finds that school can be fun.

When Emma's grandmother, who takes care of her after school and takes her out for bagels on Wednesdays, gets sick and has to go to the hospital, Emma is afraid that she will die--but she is also afraid to talk about her fear.

Brock is worried about going to his friend's superhero birthday party alone, but while he is hiding he meets Nelly, who is just as frightened as he is.

Camila is filled with worry and fear, but when she hides during a class field trip to the aquarium, she finds a classmate who is also afraid and needs a friend.