"Sister of Aaron" may either mean that Mary had a brother of the name of Aaron, or it may mean that she belonged to the family of Prophet Aaron. The first meaning is supported by a tradition of the Holy Prophet and the second is plausible because that is supported by the Arabic idiom. But we are inclined to the second meaning, for the wording of the said tradition does not necessarily mean that she actually had a brother named Aaron. The tradition as related in Muslim, Nasa'i, Tirmizi, etc. says that when the Christians of Najran criticized the Quranic version of stating Mary as the sister of Aaron before Hadrat Mughirah bin Shu`bah, he was not able to satisfy them, because Prophet Aaron had passed away centuries earlier. When he presented the problem before the Holy Prophet, he replied, "Why didn't you say that the Israelites named their children after their Prophets and other pious men?" That is, "You could have answered their objection like this as well." (See also E.N. 32 of Al-i-Imran).
How can the people who reject the miraculous birth of Prophet Jesus, explain why Mary's whole community had come out to curse and condemn her when she had appeared before them with the child?