A.D.
This is common in someone your daughter's age, but it could definitely have been brought on now by the addition of the new baby. While the "easy way" to get her to go to sleep, is to have your husband lay down with her, this isn't going to help her fall asleep on her own or give her any way to handle waking up in the middle of the night.
Also, it will be harder for her to handle things if the new baby is in your room - how come everyone gets to sleep together but me? I'm not saying to change this if he is, I'm just throwing kid logic out there.
I think your husband should read her a story and then tell her he's going to pat her back while she falls asleep. He can tell her that mommy and daddy are right here, we're not going anywhere, but that she needs to sleep in her bed and he needs to sleep in his. Work out a system, and be consistent. (it will take awhile) I do like the idea of putting a sleeping bag in your room. You can tell her if she wakes up in the middle of the night that it's ok to come into your room and curl up in the sleeping bag, but that you don't want her to wake you up. (just don't have the sleeping bag where you can step on her)