This book's inspiration came from real-life news about an elderly woman who for five years waved every day to kids on their school bus, with them waving back. When she had to spend time in rehab, they sent her a big photo of them waving, and when she returned, they greeted her with a "Welcome Home" sign, cheering, and honking horns.

In the book, Mateo heads on the bus to a new school, feeling left out as old friends greet each other. He thinks he sees a hand the window of a purple building they pass, and on the way back he looks more closely. Sure enough, there's a waving hand and a smiling face, and Mateo encourages everyone on the bus to wave back. A classmate tells him, "You made that grandma very happy," and from then on, this student and her friends save a seat for Mateo.

The story continues in this vein, with kindness building friendships and friendships nurturing kindness, spreading wider and wider circles of happiness and belonging. Christy Tortland's illustrations reinforce this sense of inclusion by showing children of different races and a student wearing a hijab.

Eventually, the kids visit and boost Grandma's spirits when she becomes ill and needs to spend time in a nursing home. When she returns to her community, many elder friends join her in waving to the kids on the bus.

The 2023 U.S. Surgeon General’s Advisory, "Our Epidemic of Loneliness and Isolation," noted that over decades and across many measure, Americans appear to be becoming less socially connected. This valuable book for five-to-nine year olds shows ways to reverse that trend and strengthen ties with each other, in daily life and in times of crisis.