Appears 4 times in the Quran. (Root: اخو)
  1. Allah enjoins you concerning your children: The male shall have the equal of the portion of two females; then if they are more than two females, they shall have two-thirds of what the deceased has left, and if there is one, she shall have the half; and as for his parents, each of them shall have the sixth of what he has left if he has a child, but if he has no child and (only) his two parents inherit him, then his mother shall have the third; but if he has brothers, then his mother shall have the sixth after (the payment of) a bequest he may have bequeathed or a debt; your parents and your children, you know not which of them is the nearer to you in usefulness; this is an ordinance from Allah: Surely Allah is Knowing, Wise.

  2. They ask you for a decision of the law. Say: Allah gives you a decision concerning the person who has neither parents nor offspring; if a man dies (and) he has no son and he has a sister, she shall have half of what he leaves, and he shall be her heir she has no son; but if there be two (sisters), they shall have two-thirds of what he leaves; and if there are brethren, men and women, then the male shall have the like of the portion of two females; Allah makes clear to you, lest you err; and Allah knows all things.

  3. And Yusuf's brothers came and went in to him, and he knew them, while they did not recognize him.

  4. The believers are but brethren, therefore make peace between your brethren and be careful of (your duty to) Allah that mercy may be had on you.