If the Parent has no child or the New Child is to be first (Black Lines) #A1 New Child’s sibling is set to the Parent’s child, which may be null. #A2 Parent’s child is set to the New Child. This removes existing link to previous child. Otherwise place in order or at end (Red Lines) #B1 New Child’s sibling is set to the Child’s sibling, which may be null. #B2 Child sibling is set to the New Child. This removes existing link to previous sibling. |