Sahih Adab al-Mufrad

Narrated from Sayyiduna Usama bin Zaid (may Allah be pleased with him) that the child of the daughter of the Messenger of Allah (peace and blessings of Allah be upon him) became very seriously ill, so his mother sent a message to the Prophet (peace be upon him) that my son is at the throes of death. The Prophet (peace be upon him) said to the messenger: "Go and say to her: «إن لله ما أخذ ، وله ما أعطى ، وكل شيء عنده إلى أجل مسمى ، فلتصبر ولتحتسب .» 'To Allah belongs what He takes and to Him belongs what He gives, and everything with Him has an appointed term, so she should be patient and seek reward from Allah.'" The messenger went back and conveyed your message to her. She sent another message to you and made you swear that you must come, so the Prophet (peace be upon him) got up with some of his companions, among whom was Sa’d bin ‘Ubadah. The Prophet (peace be upon him) took the child and placed him on his chest. The child’s chest was making sounds like the sound of water dripping from an old water skin. Tears flowed from the eyes of the Messenger of Allah (peace be upon him). Sa’d said: Are you weeping, even though you are the Messenger of Allah (peace be upon him)? The Prophet (peace be upon him) said: "I am only weeping out of mercy for him. Allah only shows mercy to His merciful servants."