What is a half-first-cousin?
Half-first-cousins are the children of half-siblings. Where full first cousins share a set of grandparents, half-first-cousins share only one grandparent, because their parents shared only one parent. Genetically they're about half as related as full first cousins.
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FAQs
How many grandparents do half-first-cousins share?+
Just one — because the two siblings linking them were half-siblings.
Does the calculator store my family details?+
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