AncestryDNA kits -- experience? results?

[Anonymous]

My nephew knew that his mom (my sister) was 19 when she had him and was adopted by his dad when they married. He also knew he was the result of a one night fling after a party. So 23 and me were no surprise (although, oddly, the "possible" family tree it presents shows him related on his mom's maternal side to a cousin we have on the paternal side (this might go back some generations to scandinavian origins on both sides). The surprise came when someone from the old neighborhood got a kit for christmas from his wife and learned that his recently deceased dad was not his dad and he had a half-brother--my nephew.

Turns out that when the neighborhood guy and my sister had their one night thing, he was engaged to someone else, but ALSO had another one night fling with another young woman--the half brother was born within 3 months of my nephew's birth.

The upside of this: it was a rural neighborhood, very small towns and farms, and there have always been rumors about who had secret relationships with whom. It wasn't until both our parents were dead that my sister was able to more or less confirm something she suspected based on hints--our dad fathered a son with a local woman, her parents raised the boy, she later married, the boy was killed in Viet Nam. She got more detail from her best friend from high school who got the details from a relative.

In communities like that, these kits might go a long way to prevent unintended marriages of close relatives.