Writer Jeanne Safer writes that conflicts among siblings are as old as time — and even written into the Bible, in the Book of Genesis. Safer concludes that toxic sibling relations are natural. She says siblings are not required by God, therapists or society to get along just because they are related. What do religions, and particularly Islam, teach in their stories about siblings? Are relationships generally bad? How can one overcome wrongs — perceived or real — done to them by another sibling?