I have tried my 10 month with a 20 month in one nap room two playpens and found they interact and keep each other awake. I'm having the same struggle managing where to put different age groups to sleep. It's hard. I use a monitor in the nap room, one in my daughters room and leave the daycare door open for the 4 year old having quiet time. Im always down the hall doing some admin or paperwork etc. Good luck!