DD is 15 months old and has been a great sleeper since about 4 months old. We had to do modified CIO (at 4 months) to get her to be able to fall asleep on her own, but after that she's been great. All of a sudden, in the last week and a half, she's started screaming about a half hour after bedtime and has stayed awake (crying on and off the whole time) for the next couple of hours.

Tonight has been the worst so far--she wouldn't go down at all, and started crying during her bedtime sippy of milk. She's screaming bloody murder--like, the make-yourself-sick kind of scream--and will not calm down even when we're in the room. She wants to be held for a second, and then wants down, and then runs to her bedroom door and asks for help getting out.

I don't know if she's scared of something, if this is just a phase, etc. Other possibilities are teeth (I guess, but she's napping fine at the sitter's), an ear infection (same as teeth--but we could always get it checked out), and....I don't know what else. Help?

I'm 10 weeks pregnant and she's also been really clingy lately, but I don't know if that could have anything to do with it.

Has this happened to you? Please say it didn't last long.