The face of kindness is something that's easily recognized when we see it in action, but children learn by doing and having a role. The positive effect of kindness reinforces more kindness, and over time, children discover that when you're kind, people want to play with you, invite you to come over and be your friend.

Social reward is a powerful motivator, but the core value underlying kindness is how good it feels to be nice without expecting anything in return.