Brody Jenner has revealed in the latest episode of Keeping Up With the Kardashians, that his brother Brandon and his step-sister Kim Kardashian, once shared a kiss.

Brody revealed the secret during a family vacation in Thailand, where Kim’s mum was teasing Brody for having a crush on Kim.

The 30-year-old walked in on Kim during a racey photo-shoot, where he joked about being turned on after the incident.

"I feel like Brody is crushing on Kim. I think you've had a crush since you were 7 years old."

Brody denied ever having feelings for Kim and then revealed that it was in fact Brandon and Kim who once kissed each other, when they were much younger.

"That was him and Kim!  You're forgetting that. They kissed back in the day."

Brandon then tried to change the subject but to no avail.

Brody continued to tease his brother about it: "It's on you now! And he knows it's true."

Hmmm, we wonder what Kim has to say about this kiss story.