Hi Kaliandra -
Have you done any sort of pre transitioning this pregnancy for them at all? What are you hoping for after the babe comes? You all sleep in same room/same bed/kids put themselves to sleep by themselves?
What ever it is, definitely get the routine down NOW before baby comes or else you will have to deal with some added resentment.
I have 3 kids and we still co-sleep somewhat. I don't know what advice I really can give but I'll tell you what works best for us and maybe it will be something new that can help you.
I transitioned them to putting themselves to bed by reading books by the time they were 2-3, and the third one just kind of always put herself to sleep cause that was modeled by the other two by the time she was two years old.
At 5 and 2 you can probably explain to the girls that its quiet time and let them look at books in a dimly lit room (yours or theirs or an airmattress on the floor or however you want to arrange it) and give them as long as they'll take winding down by themselves.
I would definitely teach them to wind down by themselves first in whatever their new environment is. Often times I will read a book/chapter to them (Mrs Piggle Wiggle lately) or play soft *soft* music very low.
As the kids got older it became a treat to sleep with Mommy and even lately, they have an air mattress that we put on the floor of the bedroom for them to still sleep near.
They are flexible, and will sleep in their own beds also.
Whatever your goal is, start it now -- and get a routine for bed...You all can transition in no time! :) Best of luck!!!
(PS) To have a neat variety of books, trips to library during the week are awesome and help give a 'field trip', expose the kids to books and libraries, and have the added bonus of new bed time material. :)
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