Oh, for my 'interval' sleepers, they do not know that I am checking on them, because the second they realize that I am there...it is back to square one. But I think that you are right, I need to put the boy with Williams into his own room and keep my son in his own and the other four need to tough it out together.
But let me tell you! My 2 'interval' sleepers (who are my only fulltimers) slept AMAZING today as their nap time buddies are not here on Wednesdays.