What is the distribution requirement if one heir admits the existence of another brother from the father?
Chapter on Distant Kindred (Dhawu al-Arham)
Al-Mughni
Book of Inheritance Shares (Farā'id)
Primary text
If an heir admits to having one brother from the father, he must give half of what is in his possession to that brother. This is the position held by all jurists. If he subsequently admits another brother, and both admitted brothers agree on this second admission, they must each give him one-third of what remains in their hands. This ruling is also universally accepted. Evidence is derived from the principle that the admission (Iqrar) of the possessor concerning the rights of others must be honored.
Supporting text
If the second admitted brother denies the lineage established by the first admission, the lineage of the second admission does not become established. The one who made the admissions cannot give more than one-third of what they possess, as they did not admit to owing more than that amount.