When the girls got unappreciative by telling the adults to do things without even asking, and without even saying thanks, Danny decides to teach them a lesson using a game that the adults are kids and the girls are the adults for a day. When they switched roles, the girls got their lesson when they had to make lunch for the adults and the adults were being picky on purpose.
ThIn the middle of the episode, there was the part when Danny imagined what would life be like 30 Years from that time, if the girls were still living in the house. The adults as old people was a little creepy, but Becky was hilarious (watch to find out). The girls fully grown were also slightly weird, but funny, especially Michelle.