Beloved author Rachel Vail's newest series, about an earnest young dinosaur who tries as hard as he can and his frazzled mother who always knows how to save the day.

What time does a Tyrannosaurus rex go to sleep at night? At bedtime! But tonight Mama Rex is working on an important project for her job. She needs T to be quiet. Most of the stuff that T does is noisy. So Mama Rex comes up with an idea: T can stay up late...as long as he is quiet and helpful!
Will T keep his part of the bargain? Find out in this funny and charming story.