But the mystery of Khloe's out of place looks may have just been explained by an exclusive in Star magazine.
The widow and ex wife of Robert Kardashian have both come forward claiming the late father of Kim, Kourtney and Khloe expressed doubts over the paternity of his youngest daughter.
"Khloe is not his kid - he told me that after we got married," Jan Ashley, 63, the woman who married Robert after Kris Jenner, reveals to Star.
Ellen Kardashian, 63, married Robert in 2003 just two months before his death from cancer. She says her late husband suspected Khloe was the result of an affair Kris Jenner had before their marriage ended in 1990. And he even told her he wasn't sleeping with his wife any more by the time Khloe was conceived.
"Khloe brought it up all the time," Ellen tells Star. "She looked nothing like the rest. She was tall, had a different shape, light hair, curly hair. Didn't look anything like the other three children."
"Robert did question the fact that Khloe was his," she adds. "Any normal man would if they knew their wife had cheated on him."
"[But] he never would have considered a DNA test. He loved her very much."