Musannaf Ibn Abi Shaybah

Hazrat Abu Laila narrates that once we were sitting with the Holy Prophet (peace and blessings be upon him) when Hazrat Husain bin Ali (may Allah be pleased with him) came crawling on his knees and climbed onto the blessed chest of the Prophet (peace and blessings be upon him) and urinated. We quickly moved forward to catch him, but the Prophet (peace and blessings be upon him) said: "My child, my child." Then he called for water and poured it over the spot.