The bond between siblings is one of the most common yet least understood types of relationships. For some, a sister or brother can be a lifelong source of comfort, reassurance, and love. But for many others it can be a constant stream of resentment, anger, and rivalry. Differences in temperaments, personalities, interests, and ages can fuel unrest between siblings, but teaching them how to work through their problems is an excellent way to prepare them for life’s more difficult moments.