L.H.
We went through this with my step son at that age. When he turned 4 it was time for him to sleep in his big boy bed. My husband would lay with him until he went to sleep (and still has to now that he is 6). It has worked except that he still can't go to sleep in his own. You might not want to start that but my husband enjoys the alone time that they get to have before he falls asleep. Be consistent. If you let her sleep in your bed sometimes, she won't understand why she can't all of the time. She should sleep in her own bed, as well as get ready for bed, in her own room every night. Maybe have her help you pick out a new nightlight and new stuffed animal to sleep with. Make a big deal about it when she does a good job and give her lots of praise. Its tough but stick to your guns! Good luck.