No. The fact that you have 10% Irish and your brother has 40% does not mean you don’t have the same father.
What many people don’t understand is that DNA does not pass evenly to children.
It’s like a deck being shuffled and each child gets it as it lands. While a parent will pass 50% of its DNA to each child, it won’t be the exact same 50% to each.
That’s why one sibling can be 40% Irish and other not have any. While the roots may be the same, the DNA does not pass the same.
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