Note 22 (Quran Ref: 19:28 )

In ancient Semitic usage, a person's name was often linked with that of a renowned ancestor or founder of the tribal line. Thus, for instance, a man of the tribe of Banu Tamim was sometimes addressed as "son of Tamim" or "brother of Tamim". Since Mary belonged to the priestly caste, and hence descended from Aaron, the brother of Moses, she was called a "sister of Aaron" (in the same way as her cousin Elisabeth, the wife of Zachariah, is spoken of in Luke i, 5, as one "of the daughters of Aaron").(Quran Ref: 19:28 )