MUSLIM GRANDPARENT'S INHERITANCE SHARE
Under Muslim succession rules, the Father of Father (i.e., Grandfather) inherits the share if Father does not survive. Father of Father inherits one-sixth (i.e., 1/6) share. Father of Father receives additional Residue (i.e., One-sixth + Residue) if Sons and Sons of Sons how low soever do not survive. Mother of Father (i.e., Paternal grandmother) and Mother of Mother (i.e., Maternal grandmother) inherit if Mother does not survive. Mother of Father inherits one-sixth (i.e., 1/6) if no Mother and no Mother of Mother survive. Mother of Mother inherits one-sixth if no Mother and no Mother of Father survive. Mother of Mother and Mother of Father inherit one-twelfth (i.e, 1/12) each if Mother does not survive. Paternal Grandmother (i.e., Mother of Father how high soever) does not inherit if Father survives as per Hanafi, Shafii, and Maliki but does receive a share as per Hanbali. To note that as far as the grandmother is concerned, she will either be deprived completely or takes her share. Any reduction due to a number is not called "Reduction" in Islamic inheritance law jargon, as it could happen to everyone.
Refer to "Islamic inheritance sharers and residuary" to learn more about grandparents' shares. Refer to "Islamic Inheritance Blocking Rules" to learn more.
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