My 19mo dd has always been a really good sleeper. She learnt to suck her thumb early on and so has self settled since she was about 6 months, and also has a bunny rabbit as a comforter. Up until now we could put her down in her cot awake, leave the room and she would suck her thumb and go to sleep. However, in the last week she has started to refuse to lie down in her cot. When we put her in, she sits up and screams. The only way I have found to get her to go to sleep is to lie down next to her cot on the floor. She still refuses to lie down but will suck her thumb until she is virtually asleep sat up, like a little drunken sailor, and will finally lay down and sleep. This has to be repeated every time she wakes up in the night, 4 to 5 times a night when she never used to wake at night, and would easily sleep 10 to 11 hours. We have tried taking the side off of her cot to see if that was the issue, but no difference. I also tried timed cc, waiting 4 mins, 6 mins etc but she just got hysterical. It's clear she wants to go to sleep but is struggling. She never tries to get out of her cot even with the side off. She's currently in a sleeping bag as she refuses duvets or blankets of any kind. Has anyone been through this? Is it a phase? Are we making things worse for ourselves by laying with her every time she needs to go to sleep?