Under mother property distribution in Islam, the division is fixed that go to grandmothers. Muslim grandparents receive under Islamic law when parents do not survive in general. There is certain Hajb (i.e., blocking or exclusion) rules are applicable for ascendants of Grandparents.
Under Muslim succession rules, the Grandfather receives the share if Father does not survive. Grandfather receives one-sixth (i.e., 1/6) fixed or prescribed share. Grandfather receives additional Residue (i.e., One-sixth + Residue) if Sons and Sons of Sons how low soever do not survive.
Paternal and Maternal grandmothers receive if Mother does not survive. Mother of Father receives one-sixth (i.e., 1/6) if no Mother and no Maternal grandmother survive. The Grandparent's share can vary in certain conditions due to the decrease or increase of total shares under the Radd and Awal (or Aul) scenario.
The Maternal grandmother receives one-sixth if no Mother and no Mother of the Father survive. Maternal and Paternal grandmothers inherit one-twelfth (i.e., 1/12) each if Mother does not survive. Paternal Grandmother does not inherit if Father survives as per Hanafi, Shafii, and Maliki but does receive a share as per Hanbali.
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 law jargon, as it could happen to everyone. You can see the Parents and Grandparents chart for more information.
If Husband left with Wife or Widow, Husband's Grandparents will be eligible for division. If Wife left with Husband or Widower, Wife's Grandparents will be eligible to receive division. This feature is unique under Muslim succession law; you may not find many other laws.
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