Dd 11 months has been sleeping through from 8-8/9 for last few months. For the last week she suddenly won't go to sleep in her own cot and when she eventually falls asleep and we put her to bed it's for no more than 2 hours! She's fine during the day has one nap at around 1ish and is behaving normally. What on earth has happened to my baby? She screams like a banshee at bed time regardless of how tired she clearly is