So my son has recently expressed an interest in camping with me. He is 5 years old, almost 6. I've been waiting for some nicer weather so we could give it a try in the back yard to see how he likes it, figuring that'd at some point of the night he'd be begging to go back in the house.
I finally gave up waiting for good weather as we were both getting impatient and so I dug out my 4 person Coleman tent and set it up in the back yard. I built us a nice fire and we did all the usual stuff, s'mores and hot cocoa, etc... The night was cold here, about 23F for a low, so my wife was very worried, but I purchased him a nice Lodge River Jr 0° bag, and had a cheap 40° rectangle bag I could open up and cover him with like a blanket.
Surprisingly enough he crawled right into the bag and fell asleep about halfway through me reading him his library book. I think he slept better than I did (not used to the ground anymore...) and I kept waking up to check on him to make sure his face wasn't getting covered up too much or something.
He woke up once around 5 am when our neighbor's rooster started crowing, and again around 7 when the sun lit up the tent.
He made me very proud, had fun throughout and never once even considered going in the house. He wants to do it again soon in the hammock, then he'll be graduating on to "woods camping" instead of "yard camping".