Where can I find information on sibling separation issues?

I had already searched google and some of my college data bases, but I still can not find the information I am looking for. I am trying to find information on the affects of sibling separation, specifically the type that I have gone through. I have not lived with my little sister since I was in the 7th grade, and have had very little contact with her. She is now 15 and I’m 19 but we have not lived with each other, and have had constricted communication because of complications with her father. I want to find information on situations like this, or situations that involve siblings living apart from one another.