I used Google Blog Search to find the following blog article. It is from the Children's Literature at the Education & Social Services Library. http://www.library.illinois.edu/blog/esslchildlit/archives/2008/08/sibling_rivalry.html
I found this article to have relevance to my blog's theme, as it is important to find books that children can relate to. This article shows a list of various books regarding the theme of sibling rivalry, and lists books for all age groups.
As the article states, "Conflict between siblings is a universal theme. Stories about famous siblings from Cain and Abel to Venus and Serena Williams have captivated people throughout the centuries. The following books explore the frustrations of sharing Mom and Dad's attention, dealing with annoying younger brothers and sisters, and learning to appreciate each other."
Having books available that interest children gets them reading and engaged in the task. This is important, not only for young children who are learning to read and are experiencing a new sibling into the family, but for middle ages and teens as well where these issues are still prevelant, and, perhaps, more difficult.