Brody Jenner can’t stand The Hills’ Spencer Pratt, but he loathes Spencer’s younger sister, Stephanie, even more!

“If Spencer’s a creep, multiply that by 10,000 times and you’ve got Stephanie Pratt!” Brody, 24, said at Ryan Sheckler’s X Games Celebrity Skins Classic on July 29 in Rancho Palos Verdes, Calif. “She’s way worse than him, and he’s no prince.”

But Stephanie, who has had her share of catfights and on-screen feuds, claims she doesn’t know why Brody is so annoyed by her. “I’ve never done anything mean to Brody,” Stephanie, 21, tells In Touch. “So, I don’t understand why he continues to attack me.”

Although she denies it, Brody is mad that Stephanie reportedly hooked up with Lauren Conrad’s ex Doug Reinhardt on the upcoming season of The Hills.