Proverbs 17:17 A friend loves at all times, And a brother is born for adversity.
When you say you are a friend to someone, how deep do you mean that?
A friend should be someone who is willing to be there at all times, willing to be called in the middle of the night, willing to turn up when needed.
A brother is one who will be there when they see trouble approaching, one who will be there during the night and will support you when they see you may need it.
A brother exists to fulfil the role of comforter even when we do not ask. The Holy Spirit is our great comforter who is more than a brother!