[Devora]

Do you have Over the Moon by Karen Katz? The text isn't my favorite in a couple of spots, but it's decent. The pictures are colorful and it would help walk her through the process -- It starts with waiting for the phone call saying they can go get their baby, going to the airport and flying, meeting the baby, then coming back home. It includes a brief explanation about the family who took care of the baby and the fact that the baby has another mother (that's the part where I change the text to use language that I prefer).

It sounds like the coming back home may be a big part of her anxiety. The fact that the book shows the parents leaving and coming back might help.

Too, the fact that it shows the foster parents but it's clear that the adoptive parents are now the mom and dad might help.