4

The advantage of more people testing is that you can use the cM ranges better. Here, your aunt matches full siblings with different cM totals, even though they have to be the same relationship to her. You are looking for relationships where both 503 and 348 cM are within the range. Using the Shared CM Project, these include: Great grand aunt/uncle. Great ...


2

It absolutely means that your half aunt is not biologically your half aunt or another close relative. There are 4 possibilities: Your father's dad is not his biological dad. Your aunt's dad is not her biological dad. Your dad is not the biological dad of either you or your sister. There is some sort of error at Ancestry.com. If you're checking your ...


1

Check out the Shared cM chart to see the possibilities relationship around 1148 cM. It could be half niece/nephrew, niece/nephrew, great-niece/nephew, grandchild, and so on. You have to use genealogy to confirm the relationship. You do this by starting with the birth year of the match. Then try to fit them into your tree to confirm the relationship. My ...


1

Too high to be a half cousin. You share about 12.5% with a cousin and 6.25% with a half cousin. Sorry to burst your bubble but it's better to be honest, there's very little chance that that would be a half cousin.


1

From the The Shared cM Project 4.0 tool v4 a match of: 758cM between you and your half uncle has a probability of 86%. 456cM between you and your half great aunt has a probability of 86%. For your sister a match of: 500cM between her and your half uncle has a probability of 5%. 590cM between her and your half great aunt has a probability of 78%. While ...


1

DNAPainter is the tool for you. For 758cM, it lists several possible relationships."Half Aunt/Uncle" is one of them, so yes - that could be the relationship. But it lists several other possible ones - some of which I'm sure you can eliminate given what you know about your family.


1

I assume that you're talking about the daughter of a half-sister here. Half-sisters with a father in common will inherit the same X-chromosome in its entirety. A biological daughter of either of them will inherit some recombination of her mother's 2 X-chromosomes, so there should be significant x-DNA in common between the daughter and each of the half-...


1

From your description, your paternal grandfather had two wives. One is the mother of your father and the other is the mother of your aunt. @cyn's point Your aunt's dad is not her biological dad is the most likely scenario. I would look for a previous marriage for your aunt's mother or a birth record for your aunt in her mother's previous married ...


1

If your father's "half sister" is expected to share a father with him then one alternative may be that your father has his expected father but his "half sister" does not.


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