(Their father, the late Robert Kardashian, was part of Simpson's legal team; Jenner was one of Nicole Brown Simpson's best friends before her unsolved June 1994 murder.)
"Now we have all the answers! It makes sense now!" Kim, who is of Armenian descent, joked on Twitter Wednesday. "Khloe, you are so tan."
Ironically, Khloe took a DNA test during an April 2009 episode of Keeping Up With The Kardashians to prove she was not adopted.