this is the 6th night in a row that my 16mo ds has been refusing to go to sleep in his cot. he is normally brilliant at bedtime, we have a routine and he is usually down at 7 and asleep by 7.15, rarely any tears or fuss. Last few days he has become hysterical when I put him into his cot. As soon as I pick him up he stops crying. Just to get him to sleep the last few nights I have put him on the bed, he's gone off to sleep perfectly happily and 30 mins later when he's fast asleep I've moved him into his cot. But tonight I really want to sort this out and he has spent the last 30mins crying to the point of hysteria - though he stops instantly when I come in and starts the instant he goes back in his cot or I make him lie down, which I have done twice so far. I am typing this to the background noise of his miserable sobbing and crying.
He's not ill, hot, teething or anything else obvious. I feel awful for leaving him to cry but I want my compliant happy bedtime baby back! and the sleeping on the bed routine is not one I'm prepared to make permanent.
any ideas why this is happening and what I can do to sort it out please?