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Can one claim British citizenship if mother and maternal grandparents and brothers and sisters resided in a British overseas territory (Montserrat), or if first and second-generation aunts/uncles, mother brothers and sisters reside in England for many years now
Additional Details
Some more:

Grandfather's mother from: Montserrat

Great-aunt living (with family) in: England

Grandmother's sister living in: Brighton, England

Mother born in Montserrat 1952
Grandmother born in Montserrat 1921
Grandfather born in Meade John 1922

Only parents can pass on British citizenship to their children, and that also if the law allows them to.

See also British citizenship "by descent" and "otherwise than by descent".