It is narrated from Hazrat Usama bin Zaid that when the daughter of Hazrat Zainab was brought to the Holy Prophet (peace and blessings be upon him), tears came to his eyes. Hazrat Zainab was gasping for breath, as if she was in old age. Seeing this condition, the Holy Prophet (peace and blessings be upon him) began to weep. A person said: O Messenger of Allah (peace and blessings be upon him)! You are weeping, even though you have forbidden weeping? The Holy Prophet (peace and blessings be upon him) replied: These are tears of mercy which Allah Almighty has placed in the hearts of His servants. Surely, Allah is merciful to those of His servants who are merciful to others.