Sayyiduna Dhirar bin Azwar (may Allah be pleased with him) says: Some of my family members sent me to the Noble Prophet (peace and blessings be upon him) with a milch she-camel. I brought it to him. The Prophet (peace and blessings be upon him) ordered me to milk it. Then he said: Leave (some) milk in the udder that will be a cause for (more) milk to come.