At two years old and talking, she's not really a "baby" anymore and is capable of a lot more than you probably think. If she's sleeping in a "big girl" bed at her dad's house, and a "baby" bed (crib) at your house, she's probably picking up on that. When you first transition her to a big bed, she's going to take advantage of her new freedom and get up, play, roam around, etc. The other suggestion about taking her by the hand and putting her back in bed (no talking) is a great one. It's worked for me, and for a lot of other people I know. And it keeps coming up on this site in response to your same kind of question. If they share a room, splitting up bedtimes is a good idea, although if you ever want them to go to bed at the same time in the future, I would recommend putting them to bed together now. It would be just as easy (or hard) to train them both that it's not time to play at night as it would to train the little one that it's time for bed and stay in bed. I have twin boys that are two and a half now and have been sleeping in the same room in twin beds since they were 15 months old (because we moved and got rid of one crib, not necessarily because they were ready). I had to deal with both issues (staying in bed, and keeping each other up) at the same time. They still don't always stay in bed right at first, but they always end up asleep in their beds within a relatively short time. My now 17 month old has been sleeping in a big girl bed (twin mattress off the frame and box spring) since she was 13 months (because she was ready to and wanted to be like big brothers and sister), and almost always falls right to sleep in bed without getting up. She's gotten up maybe twice in those 4 months. Of course, she's had three older siblings to learn this from. Plus she has that kind of personality anyway. My oldest was out of a crib and into a big girl bed at 18 months because we moved and were going to need the crib in six months so we were trying to make the transition from "her" crib to "baby's" crib easier. So I'm just saying that it's not impossible. It just takes a little bit of effort and consistency on your part. So really, it's up to you whether she stays in bed or not. My one piece of advice for you personally though, is to put her in a big bed at your house. This is because she already has a big girl bed at her dad's house. It's probably the reason she asks to sleep in sister's bed at home now. If she only slept at one house, then I would say leave her in the crib as long as you want or until she starts crawling out. But since she sleeps in two places, and it's different in each, the consistency of having the same kind of bed at each place probably would be good for her. Good luck with it!