there are a lot of little ones who substitute for truck, it is usually the way they make their sounds. anyway, little kids can be so cute. my daughter used to run around the house naked after her bath, which annoyed her dad to pieces. I told her to stop running around the house naked and she looked up at me and said, "but Mom, I'll walk". i just about lost it laughing at her. also threatened to put it in reader's digest....