"Which one do you want to be?"

I regularly hear this question now and not just when we are reading books or watching a movie.  Collin asks this question whenever faced with more than one item.  Tonight, he asked this question:

• As soon as I walked in the door when I got home from work.  He was watching Happy Feet with Daddy and he wanted to know which penguin I wanted to be.  He was the snake.
• Saige and Linden came over briefly to play.  I heard him asking the girls which they wanted to be when he wanted to play "family".  He was the Mommy.
• When he was taking a bath and about to race the scuba diver with the boat.  He was the scuba diver...so I guess I was the boat.
• When looking at his toothbrushes before brushing his teeth.  I wanted to be whichever one did not slow the process down of getting into bed