Kourtney is doing great post break-up: Kylie Jenner

Reality TV star Kourtney Kardashian is "doing great" in the wake of her separation from long-term partner Scott Disick, according to her younger sister Kylie Jenner.

The 17-year-old reality star has assured fans that her older half-sibling Kourtney, 36, is staying strong following the end of her nine-year relationship from Disick, 32, this week, and has had the full support of all her sisters.

"Kourt is actually doing great...Everyone's doing good. I'm doing good. We're sisters. We always stick together," Kylie told eonline.com.

Kourtney, who has three children - Mason, five, Penelope, three, and six-month-old Reign - with Disick, has sought comfort in her sisters Kim Kardashian West, 34, and Khloe Kardashian, 30, since the break-up and the trio were spotted out for dinner earlier this week and out at Malibu Wine Safari on Friday.

Although neither Kylie or Kendall Jenner, 19, were at the meal, they have been constant contact with Kourtney.

Kylie added: "It was an older sister night ... but we've been talking. She's been helping me with my house a lot."