Q: Who was Asma (radhiyallahu anha) to our Prophet (Sallallahu Alaihi Wasallam)? Was she a mahram?
A: If you are referring to Asmaa bint Abi Bakr (radhiyallahu anhuma) then she was not a mahram.
And Allah Ta’ala (الله تعالى) knows best.
Mufti Ebrahim Salejee (Isipingo Beach)