Wedding bells are ringing for Kylie Jenner and Travis Scott — but not everyone is happy about it! Life & Style can exclusively reveal that Khloé Kardashian is jealous her 20-year-old sister is getting married — considering that she learned her own boyfriend-turned-baby-daddy, Tristan Thompson, was cheating on her just days before welcoming their daughter, True.

"Kylie is heading toward the perfect family life that Khloé has always yearned for," a source revealed, adding the 33-year-old isn't the only one with mixed emotions about this. Kim and Kourtney Kardashian are also on the fence, though Kendall Jenner agreed to serve as a bridesmaid on her sister's big day. Kylie and Travis have no doubt experienced their fair share of ups and downs — but they've been closer than ever since welcoming their daughter, Stormi, on Feb. 1.

Khloé and Tristan have been at odds since photos and video footage emerged in April, featuring Tristan acting unfaithfully towards his then-pregnant girlfriend. It's still unclear whether or not they'll be able to work things out — though the NBA star swore earlier this week that having a daughter "changed" him.

"I think with a girl, you’re just so much more emotionally like — with a boy, it’s just like, 'Hey, man. You’ll be alright, man. Stop crying,'" Tristan explained on UNINTERRUPTED's Road Trippin' podcast. "But with True, it’s like, 'True, it’s gonna be OK. You know, we’re right here. Daddy’s here to feed you. It’s me! Look, yeah!' It’s way different, but it’s fun, though. It changes you."

KoKo is certainly no stranger to heartbreak. She had her fair share of unfaithful boyfriends, like James Harden, back in the day — and fans will recall her four-year marriage to Lamar Odom ended thanks to infidelity and substance abuse on his end.

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