When your son comes up with THIS as a valid outfit choice.
[no joke. My son wanted to go outside at 7:30 am. My husband warned him that it was still a little bit chilly outside. Christopher came out with THIS OUTFIT a few minutes later, waddling down the hall -- as best as he could -- and said, "Daddy, I didn't have any long pants in my drawer, so I made some. I'm going to go jump on the trampolene now." After taking this picture, my dh found him a freshly dried pair of pants in the dryer. He said that the look of relief on Christopher's face was priceless!]