We have been traveling a bit with my parents, seeing the extended family. Last night as I was getting Asher ready for bed, he saw that he was expected to sleep in a Barbie sleeping bag. He started to protest, "That bed has a girl on it! I don't want to sleep in a bed for GIRLS!!!"
Not wanting a battle over where he was going to sleep, I simply told him, "Wow! You are lucky! Your daddy would be so jealous of you! You get to sleep in a bed with a picture of a girl on it! Daddy wishes he could sleep in a bed like that, but they don't make them big enough for Daddy."
It must have worked, because he went to sleep perfectly after that. No complaining, no getting out of bed, and within 10 minutes he was out for the night.