Hetty Armstrong is a widow with 4 children. The oldest is Maudie. She is 12 and trying to be a grown up. The two boys are Charlie and Abner, ages 9 and 10. They are little hellions. The youngest is 5 year old Zoe. She's a darling, but she asks a lot of questions and tells people things that she shouldn't. Hetty has an Aunt Jo who has an acid tongue but is devoted to the family.

Hetty is about to marry Gram Jordan, who is a botany professor. She wants to bring the children along on the honeymoon, because she can't be separated from them that long and doesn't trust anyone to take care of them. Gram is hesitant, but agrees. The wedding takes place in Hetty's house, where they are all going to live. Then they set out on their trip to the Grand Canyon.