Last year one of my wife's uncles had a DNA test done, and he turned out to have a sibling match with someone he had never met (living in a different country).

Last year one of my wife's uncles had a DNA test done, and he turned out to have a sibling match with someone he had never met (living in a different country). Turns out that her grandfather had a child from a relationship with someone he met before her grandmother, and none of the family had ever known