Get the lowdown on this basic genealogical term.
Q. I am a total novice as far as family trees go, and I need to know exactly what a "collateral descendant" is.
A. A collateral relative is any blood relative who is not your ancestor. So your ancestors are your parents, grandparents, great-grandparents, etc., and your collateral relatives are cousins, nieces, nephews, aunts, uncles, siblings, etc.
A good resource on this subject is a book called Dozens of Cousins by Lois Horowitz (Ten Speed Press).