Kendall and Kylie Jenner

Kendall and Kylie Jenner

Kendall and Kylie Jenner's older half-brother insists they have good heads on their shoulders.

Brody Jenner, 31, claims he doesn't worry about the teenagers, who are regularly spotted enjoying nights out with friends, including Justin Bieber, succumbing to any negative Hollywood influences and says they're "amazing" girls.

Asked if he is proud of Kendall, 18, who has carved out a successful career as a model, and Kylie, 17, the former 'The Hills' star told E! News: "Absolutely. They're great girls, they're amazing. I love them to death. They came out great."

Brody credits his stepsisters, Kourtney and Khloé Kardashian, and Kim Kardashian West for helping Kendall and Kylie to stay grounded.

He said: "They were raised by their sisters...they got to see a lot at a very early age. They've got a very good head on their shoulders."

The young 'Keeping Up with the Kardashians' beauties, who first appeared on the series when they were 10 and 12, recently admitted they couldn't remember not being famous.

Kylie, who crashed her $90,000 Range Rover earlier this month, said: "I don't think we really remember a time before the cameras."

Kendall, who recently sent a legal letter to a waitress after she was accused of throwing money in her face in a restaurant, added: "Even before the show, when we were babies -- four or five years old -- we'd be walking red carpets with our dad [Bruce Jenner]."