Sunan Ibn Majah, Chapter: The Chapters on Medicine

"I heard my paternal uncle Yahya – and I have not seen a man among us like him – tell the people that Saad bin Zurarah, who was the grandfather of Muhammad through his mother, was suffering from pain in his throat, known as croup. The Prophet (saw) said: 'I shall do my best for Abu Umamah.' Such that I will be excused (i.e., free of blame if he is not healed). And he cauterized him with his own hand, but he died. The Prophet (saw) said: 'May the Jews be doomed! They will say: "Why could he not avert death from his Companions?" But I have no power to do anything for him or for my own self.'"