It's 17:00. The house is quiet(安静). "Bob!" Mom says, but no one answers(回答).

Mom comes to Bob's room. He is not on the bed. But his model plane is on the desk. "He is not in his room, and he is not in the yard(院子), " Mom thinks. Then Mom comes to his grandparents' room. Bob likes to play with grandpa's radio. But he is not there.

Mom looks for him everywhere. But where is Bob? Mom is worried. She wants to call Dad. Then she comes to the living room to get the phone. 

"What's that?" Mom sees something black under the sofa. Oh, it's Coco, Bob's dog. It loves sleeping(睡觉) there. But what is next to Coco? It's Bob!