This story comes from an anonymous article in "Ebony" magazine . . . so take it for what it's worth.  A woman was dating a guy for about six months, and decided to introduce him to her family.  When she did, he saw her father and said, "Dad?"  Turns out the guy was her HALF-SIBLING . . . and the dad had a SECRET FAMILY on the side.  The entire family is now in shambles, and the half-siblings stopped seeing each other.