Musnad Ahmad Hadith 19696

Abu Burdah says that once Abu Musa (may Allah be pleased with him) was present in the house of the daughter of Umm al-Fadl. I also went there. I sneezed, but he did not respond to me, and when the woman sneezed, he responded to her. I came to my mother and told her about this. When my father came, he said, "My son sneezed in your presence, but you did not respond to him, and when this woman sneezed, you responded to her?" He replied, "When your son sneezed, he did not say 'Alhamdulillah,' so I did not respond to him, and when she sneezed, she said 'Alhamdulillah,' so I responded to her, because I heard the Noble Prophet (ﷺ) say: 'When someone sneezes and says Alhamdulillah after sneezing, respond to him, and if he does not say Alhamdulillah, then do not respond to him.'" Upon this, the mother said, "You did well."