Attachment theory is increasingly being considered when contemplating post-divorce parenting plans. Historically, there has been a strong emphasis on assessing the strength of the parent-child bond as well as a child's attachment style. Surprisingly little research has focused on sibling bonds and the implications for post-divorce parenting plans. This article provides an overview of sibling attachment theory, sibling attachment considerations in foster care decisions, and the limited research examining sibling attachment in divorce and parenting schedules. Several key questions are offered for mental health and legal professionals to consider when factoring sibling relations into post-separation parenting plans.