When I'm an adult

In order to get Leo to go to sleep, I often tell him that I will sleep with him for a few minutes, then I will go upstairs and clean up, and then I will come back to check on him. Tonight he said,"when I'm an adult, I will go upstairs and clean up". I said that would be great. He said, "and then I won't play with kids toys anymore". I explained that playing with kids toys is a lot more fun than cleaning up. He said, "yes, cleaning up is not fun".