This is a "read together" book by Vicki Lansky. This is an extremely helpful book both for the children and the parents involved in a divorce. I'd recommend it be read to children ages 4-10.
As a parent, read the book to yourself first. There are many wonderful tips and information geared toward helping you understand what your child's experience of the divorce may be like, and how you can help him/her transition. This story is a great story for explaining to your child that you are getting divorced from the other parent, and/or can be used as a tool to help a child process their experience of the divorce.
In this story there are two parents, and one child (Koko). The parents explain to Koko that they are getting a divorce and why. They emphasize the divorce is NOT Koko's fault, and that both parents will always love Koko. Koko explores his feelings and expresses his discontent of the situation, and struggles through the transition. The parents are comforting and help him know what to expect as his life changes. Both parents are careful to keep Koko's routines, and sensitive about when and who they inform of the divorce. Koko feels very sad and sometimes mad, but one day, he starts to feel better. He wishes his parents would get back together, but knows that is not what is best for them.
This is a must read for the divorced family.