I am not sure how well this will work, as I am unsure of the age of
your daughter...you mentioned you adopted her two years ago but this
does not tell me the age.

Anyway if she is four or older the first thing you need to do is sit
down with her and talk about why she does not want to sleep in her own
bed. Make sure you take whatever she says very serious but also make
sure she does not exaggerate anything.

Once you know this then remind them how big they are now and how proud
you are of the big kid things she has been doing. Things such as
helping to clean their room, behave so good in stores and so on. Leave
the conversation with them feeling happy and proud.

Next you will need to create a list that they will be able to look at.
The list will have four steps that you expect your child to do and
beside each step you will have a reward. Examples might be
1. dishes in sink after supper
2. pajamas on as soon as asked (no asking twice)
3.Teeth brushed
4. In own bed with lights out 8:00.

The rewards should be activities she loves to do, and have a really
special something for the number 4 step. With the list put together you
will sit down with her and ask how she likes to do each of the special
rewards you have down. Then tell her that she can have each one of
these everyday if she does each one of the steps everyday. Make the
rules very clear and ensure you highlight the rewards. Make sure the
biggest (most important) behavior change is the one that has the most
worthwhile reward - in other words sleeping in her own bed is the
biggest reward getter.

Hope this helps

Jason -
Hundreds of free activities, crafts and educational resources
http://www.funpreschooleractivities.com