The 30-year-old reality star blurted out the shock news during last night's (27.07.14) episode of 'Keeping Up with the Kardashians' after he was being teased after seeing Kim pose in a barely-there outfit.
Kim's mother Kris Jenner said: ''I feel like Brody is crushing on Kim. I think you've had a crush since you were seven years old.''
Brody denied the suggestions and was quick to hit back with a surprising accusation of his own, turning the heat on his elder brother Brandon.
Pointing to his sibling, he said: ''That was him and Kim! You're forgetting that. They kissed back in the day.''
Brandon, 33, refuted the claim, but Brody continued: ''It's on you now! And he knows it's true.''
Brandon, for his part, refused to be drawn on the subject and was quick to take the conversation in another direction.
The issue only came to light after Brody accidentally walked in on Kim posing for an intimate photo intended for her husband, hip-hop icon Kanye West.