Katie doesn't quite share

Our little friend Avi came to play with us on Saturday. He's 5 1/2 months old and lives in DC. As his mom Amanda put it, we went from "playing a zone defense to a man-to-man." Peter got Katie and I got Avi. Katie, however, was not happy about this. If I was playing with Avi, she tried to climb in my lap, if Avi had her toy, she tried to take it away from him. It was amazing to me to see what a developed little person she is, complete with feelings of envy. Don't know how and when this happens developmentally, but so interesting.