Cheating rumors still surround Keeping Up With The Kardashians stars Kourtney Kardashian & Scott Disick but now there is possibly proof that Disick is stepping out on Kardashian.

Scott Disick On Why He Hasn't Married Kourtney Kardashian 'If It Ain't Broke Don't Fix It'

An insider told OK! magazine Thursday that Kardashian went through Disick's phone while he was sleeping and noticed he had downloaded Tinder. It's an app in which users can find potential partners or a hookup with just a hookup based on their appearance.

They told the magazine Disick's excuse for having the app.

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"He says he only logged on out of curiosity and hasn't met up with anyone. But Kourtney doesn't believe him."

But it's not all bad for the longtime couple who has three children together.

Disick has managed to stay sober since his quick stint in rehab over the summer. He even made an appearance at a Las Vegas club and only sipped on water through the evening. In the meantime, he is enjoying raising a newborn, Reign, who Kardashian gave birth to in December 2014.

"There's always so much in the beginning when they're that little. Every day is such a big milestone, but this is my third time so it's just kind of a charm."

Still, Disick's recent habits have put a strain on his relationship with Kardashian. A separate insider said that their oldest child, four-year-old Mason is a big reason why Kardashian has not kicked Disick out of their home yet.

"It's very hard because Mason is obsessed with his dad and it would tear him - and the whole family - apart. They all love Scott like a brother."

Tags
Keeping Up With The Kardashians, Reality TV, E!