I've been doing genealogy long enough to know that not everyone is excited to learn about pedigree collapse in their own family tree. It can feel uncomfortable, even alarming, the first time you spot it - two lines on your pedigree chart that should stay separate, quietly merging into the same ancestor. But here's the thing every genealogist eventually learns: pedigree collapse isn't a scandal. It's math. What Pedigree Collapse Actually Is In theory, your family tree doubles