I saw the Prophet (peace and blessings of Allah be upon him) standing in front of the grave of our master Abu Bakr and Umar (may Allah be pleased with them). Their graves had a very small layer of bricks above them in the shape of a rectangle. The Prophet (peace and blessings of Allah be upon him) ordered the right side of the rectangle to be demolished so that he (peace and blessings of Allah be upon him) could be buried next to our master Abu Bakr and Umar (may Allah be pleased with them) after his death (peace and blessings of Allah be upon him) because his death was approaching. He was talking with our master Ali (may Allah be pleased with him) about his grandson, the Mahdi, but I do not remember what they talked about. During that time, the Mahdi appeared and approached the Prophet (peace and blessings of Allah be upon him) while he was crying with joy at meeting him.