LOS ANGELES - Kris Jenner is impressed by her daughters’ ‘inner strength’ and ‘thick skin’. The 62-year-old momager - who has daughters Kourtney and Khloe Kardashian and Kim Kardashian West, and son Rob Kardashian with late ex-husband Robert Kardashian, and Kendall and Kylie Jenner with former spouse Caitlyn Jenner - is proud of her brood’s strong work ethic and sense of creativity. She told People magazine: ‘’There’s a certain inner strength that the girls possess. ‘’It’s very important to have their level of thick skin.–CM