Keep the beat

Today, Nevin was rocking with the toy guitar. He walks over to me, strumming away. He pauses and looks at me. He strums some more while watching me. He strums a few times, and looks at me really hard. He strums a couple of times and gets up in my face a bit.

Finally, I start singing. He goes back to happily strumming. Glad I figured that one out.