Answer
Wa `alaykum as-Salamu wa Rahmatullahi wa Barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
1- As for adoption, in the sense of changing oneโs identity and lineage, it is prohibited in Islam. However, it is allowed, even recommended, for Muslims to take care of orphans in the sense of providing both physical and spiritual care for them.
2- You are not allowed to live with your adopted brother as is not a mahram (unmarriageable) for you. So, you have to wear the hijab in front of him.
Responding to your question, Dr. `Abdul-Fattah Edris, Professor of Usul Al-Fiqh, at Al-Azhar University, stated,
It is confirmed that adoption in the sense of changing oneโs name and lineage is prohibited in Islam. So, as long as you and this adopted brother are not birth siblings and you both havenโt shared the same motherโs milk, you are not allowed to live with him. He is not a mahram (unmarriageable) for you.
Given the above, you have to wear the hijab in front of him. Also, you canโt live with him as a brother.
Allah Almighty knows best.
Editorโs note: This fatwa is from Ask the Scholarโs archive and was originally published at an earlier date.