The ruling on inheritance for one through whom another converted, based on specific narrations.
Chapter on Inheritance of Wala'
Al-Mughni
Book of Walā' (Patronage)
Primary text
A view supporting inheritance states that if a man embraces Islam through another, he is the closest relative (Mawla) to the convert in life and death. This is based on the narration from Rashid ibn Sa'd, who reported that the Messenger of Allah (peace be upon him) said, "Whoever a man embraces Islam through, he is his Mawla, he inherits from him and pays his diya." Similarly, a narration from Abu Umamah states, "Whoever a man embraces Islam through, his wala' belongs to him." Furthermore, it is narrated from Tamim Ad-Dari that the Prophet (peace be upon him) stated regarding a man who embraces Islam through another Muslim, "He is the closest person to him in life and in death."
Supporting text
Al-Tirmidhi commented on the narration of Tamim Ad-Dari, stating he does not believe its chain of transmission is connected (muttasil).