All by himself

I heard Brian in the kitchen playing around the dishwasher.  I had taken some of the dishes out, and he closed the door.  The next thing I know, he's in my room saying, "Ink!" (Drink)  The lid to his cup was resting on top of it, like I had left it after taking it out of the dishwasher.  I asked him if he wanted some milk, and he said no.  I went to get the cup and realized that he was so excited about his drink because he had grabbed the cup, gone into the bathroom to fill it up with water (from the sink) and then put the lid on it!  I still went and got the stopper for the cup to keep it from leaking and screwed the lid on all the way.  I couldn't believe he had done that, though!