tollerence of sillyness

Good morning!

We have 5 children (4mo-8) and homeschool. Everyone has "quiet time" after lunch and reads or looks at books in their rooms. This used to be the time when my two year old (three next week) would go down for a nap. He has not been napping the past two weeks. How might you encourage him to stay in his room (at the least) through self-government. During this time I am usually nursing the baby and/or preparing/cleaning up for the last half of the day. If he does not sleep, he is very grouchy the rest of the day. If I allow him to stay out of his room, he is running into the older kids rooms. He will also not fall asleep if he is not in his room.

Thank you Nicholeen!