It is narrated from Hazrat Umm Hani (may Allah be pleased with her) that once the Prophet (peace and blessings be upon him) came to her, asked for water, and drank it. Then he handed the vessel to her, and she also drank its water. Then she remembered and said, "O Messenger of Allah! I was fasting." The Prophet (peace and blessings be upon him) said, "Are you making up a missed fast?" I said, "No." He said, "Then there is no harm."