In the beginning of 11 AH, the Prophet (s) became sick and passed away. Before he passed away, when he was very ill, he gave a farewell speech to the Muslims and advised them to be kind to one other. He also said "If I owe anything to anyone, they should come to me to ask for it or else, they should disregard it. If I have annoyed anyone, I am ready to be punished in retaliation for it".
The Prophet (s) passed away on the 28th of Safar or on the 12th of Rabi' al-Awwal 11 AH at the age of 63. It is mentioned in Nahj al-balagha that at the time of his death, the Prophet's (s) head lay on the chest of Ali (a).
At the time of his death, none of his children were alive except for Fatima (SA). All of his other children had passed away, including Ibrahim, who was born one or two years before the Prophet's (P.B.U.H) death. Ali (AS), with the help of some others, as per the Islamic tradition, washed the Prophet's (P.B.U.H) body, and shrouded and buried him in his house, where it is now located in Masjid al-Nabi.