Kylie Jenner says she wouldn't be friends with Kendall if they weren't sisters

Kylie Jenner has revealed she doesn't think she would be friends with Kendall if they weren't sisters.In the latest promotional trailer for Life Of Kylie, the 20-year-old said:

 'Kendall and I, I don't think we'd be friends if we weren't sisters.'

 However, she says as sisters, their relationship is so deep,they borrow each other's underwear. She said :

'I let her borrow whatever she wants. She always comes through and is like: "I need an outfit please", and I'll let her borrow whatever.

'And then I go over there, and I'm like: "Kendall, I need a pair of sweats to go home", and she'll give me the most uncomfortable old underwear, the worst sweats you've ever seen and anything that's so bad and old and small. And I'm like: "You're so mean."'