Ruling of Breastfeeding

Once the Messenger of Allah (may Allah's peace and blessings be upon him) entered upon me while a man was in my house. He said: O ‘Ā'ishah, who is this (man)? I replied: He is my brother from breastfeeding. He said: O ‘Ā'ishah, be careful who you (women) count as your brothers from breastfeeding, for the breastfeeding (that makes marriage prohibited) is only that which satisfies hunger