'I love their relationship,' Kourtney's sister says.
On Thursday's episode of The Ellen DeGeneres Show, Kim gushes about her older sister's blossoming new romance with the drummer and longtime family friend.
"I love their relationship. They've grown so much together. ...Just to think that they've been neighbors and friends for almost 15 years. Neighbors for, like, a decade," Kim remarks on the couple, who started dating in January.
It doesn't seem like Kourtney and Travis' non-stop PDA bothers her sister at all.
"It's so cute, isn't it?" Kim tells host Ellen.
"It is, but it's a lot," Ellen quips back.
"It's a lot, but it's so cute," Kim insists.
As for all the making out, Kim is here for it, adding, "You know what, that's what they do. And it's so cute and I love love, so I love them."
Since wrapping Keeping Up With the Kardashians this year, the family has spent time away from the cameras and is now preparing to embark on their new Hulu reality series.
"This is the longest we haven't filmed for," Kim says. "And it's crazy since we've had this free time, all of the stuff that's gone on. Whether it's this relationship or Kourtney's relationship or whoever's. It's like, people have had this free time off and had these beautiful new relationships blossom and it's going to be really fun and interesting to see filming dynamics and us back together. I'm excited."
As for whether Travis will be featured on the show after Kourtney has opted to keep some of her personal life private in the past, Kim has high hopes.
"I honestly haven't talked to them about it, but I'm assuming because he's such a big part of Kourtney's life that hopefully they will be on," she says.
In a recent profile for Nylon magazine, Travis told the interviewer that he wasn't sure if he'd be featured on the family's new show -- but that doesn't seem to be an issue for the pair.
"Kourtney and Travis have grown even closer since traveling together. They have gotten so much more serious, to the point that they could very well spend the rest of their lives together," a source recently told ET. "They are both very committed and very happy. Their kids are also excited about a bigger, closer future together."
Scott Disick Has 'Unsettled Ill Will' Towards Kourtney Kardashian and Travis Barker, Source Says