I have 5 under three sleep in the playroom. The three 2 year olds and one 21 month old sleep in cots. The 20 month old will be a few months yet I think before I transition to a cot. All but one have stayed in bed. First time he scaled the pack'n'play, I got out the cots. I did have one nap a few weeks after that were I had to put him back in bed 5 times. All has been smooth otherwise. They all started napping together in the playroom, so it is what they are used to. I set up the video monitor so I can view and talk to them if needed. In my old location I used different rooms for each and I much prefer this. It can work