My two year old literally fell asleep halfway through supper. Just had droopy eyelids for 30 seconds then plonked his little head on the table and refused to wake up again (but he is responsive). He has no particular reason to be tired. AIBU to be worried. He doesn't have any other signs of being ill but I've never seen this before and it's quite out of character for him (usually only sleeps in the car/after prolonged breastfeeding).