This is what my brother loves to do if he's over late at night when Shea is sleeping. Play with his Lego. In this case, setting up a scene of Lego Star Wars people for Shea to find in the morning. Shea never knows what to make of this. He's partly excited that his uncle is setting up his Lego, but partly annoyed that someone played with Lego without him.
Graham is nearly thirty. How old are you when you stop playing Lego, anyway???