Maryam Was Neither the Biological Daughter Nor Sister of Prophet Haaroon
1-9-2020 | IslamWeb
Question:
Salam. I am a bit confused. I read fatwas about Maryam and her parents and I still don't know if Maryam, the mother of Isa, was the actual daughter of Aaron or his actual sister? And who was Imram and Harun? Is it true that Maryam had a half-brother? How many siblings did she have? What was their names? Please provide clear evidences.
Answer:
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad 
is His slave and Messenger.
There is no doubt that Maryam (Mary), daughter of ‘Imraan, was neither the biological daughter nor sister of Prophet Haaroon (Aaron), brother of Prophet Moosa (Moses), may Allaah exalt their mention all. Ibn Katheer 
said in Al-Bidaayah wa An-Nihaayah: “Muhammad ibn Ka‘b Al-Qurathi made a mistake when he claimed that she was the biological sister of Moosa and Haaroon because they lived in distinctly different ages, separated by a very long time, as evidently known to the least person who has the knowledge to refute this utterly wrong opinion of his.” [End of quote]
As for the Saying of Allah, The Exalted, (which means): {O sister of Haaroon…} [Quran 19:28] scholars of Tafseer held several opinions, the preponderant of which is that Maryam had a brother named Haaroon, as it was common among the Israelites to name their children after Haaroon, brother of Moosa, to seek the blessing. It was narrated that Al-Mugheerah ibn Shu‘bah 
said: “When I came to Najraan, they (the Christians of Najran) asked me, ‘How come you read in the Quran (what means): {O sister of Haaroon}, whereas Moosa lived way longer before ‘Eesa (Jesus)?’ When I went back to the Messenger of Allah, I asked him about that, and he said: ‘They used to name their children after their Prophets and pious people who had lived before them.’” [Muslim]
Another opinion suggests that the verse actually refers to Prophet Haaroon 
yet it means that Maryam, daughter of ‘Imraan, was from his descendants. This is similar to addressing an Arab as: ‘O Brother of the Arabs,’ which was common in the past. There are also other interpretations of the verse.
You asked, ‘Is it true that Maryam had a half-brother? How many siblings did she have? What were their names?’ We do not know of any Sharee‘ah text that mentions this information except for the previously cited Hadeeth narrated by Al-Mugheerah, indicating that she had a brother named Haaroon. Ibn Katheer said in Al-Bidaayah wa An-Nihaayah: “The authentic Hadeeth – referring to the Hadeeth narrated by Al-Mugheerah – indicated that she had a brother named Haaroon, and the story of her birth when her mother dedicated her to Allah does not mention anything that indicates that she did not have a brother.” [End of quote]
Allah Knows best.