Travis' reps vehemently denied the claims, but according to reports, Kylie had found evidence on his phone to suggest that he was being unfaithful to her.
So what WAS that evidence?
TMZ now claims that Kylie found some "overly friendly" DMs between him and many women on Instagram.
It was these conversations that prompted Kylie to confront Travis about cheating.
People reported that while "Kylie was upset at first," she "seems better" now.
Not long after the accusations, Travis deleted his Instagram account. TMZ reports that he deleted it to "prove his devotion" to Kylie.
His Instagram is now up and running again.
Boy, it's been a hard start to the year for Kylie. Not only did she lose her best friend to a cheating scandal with her sister Khloé, but now she has reason to believe that her own relationship could fall apart.
At least she has her billions of dollars to cry into.