Brother Confirms: Jon Feared Kate Was Having Affair With Bodyguard

Jon and Kate Gosselin's marriage is done, her brother, Kevin Krieder, says in an explosive new interview.

"Six month ago, Kate came to Jon and said, 'Hey, it's over," Krieder, 32, tells — confirming a similar sentiment a source told Us Weekly in our newest issue, on stands now. Krieder also reiterates Jon's fears that his wife of nearly 10 years was having an affair with her married bodyguard, Steve Neild, as exclusively reported by Us. (Kate has confessed she and Jon might split in the same interview she says she is "horrified" by any allegations suggesting she and Neild are romantically involved; TLC refused comment.)

Check out photos of stars caught cheating.

"Jon came to our door one day and told [Krieder's wife] Jodi he suspects it's Steve the bodyguard, and he feels that he's getting the bad rap," Krieder says. "He feels that Kate's not being faithful either." A source tells the newest issue of Us Weekly that Kate and Neild (who flew to a promotional appearance in Michigan together last night from Maryland) have a "very physical" relationship. At a recent public appearance, "she was gently poking him, giving him little love pats, totally unlike the slapping she does with Jon. She and Steve were joking around so much, I actually wondered if they were having an affair," the source goes on.

Look back at photo of Jon and Kate through the years.

Continues Krieder: "Although Jon has made some poor choices lately, he suspects that…Kate has been unfaithful. It's a horrible thing to talk about, but it just paints how bad and how different reality is from the reality show." (The new issue of Us reveals even more public trysts between Jon and 23-year-old third grade teacher, Deanna Hummel, with whom he had a three-month affair.)

See photos of Jon and his mistress.

For much more on Kate and her bodyguard's "inseparable" relationship, what people in her town say she's really like as a mom, how much money is at stake for the Gosselins, and how Jon is handling the pressure, pick up the newest issue of Us Weekly, on stands today.

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