In Touch has learned that one of the unions on season four of the FYI reality series Married at First Sight went up in smoke — marijuana smoke! — not long after the couple exchanged vows.

Derek Schwartz revealed his penchant for pot to bride Heather Seidel on their honeymoon and a source reveals that after that “it all went downhill.”

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Heather — who, as In Touch reported, was arrested for DUI In 2011 — feared Derek’s love of weed was going to become a big issue in her new life.

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FYI

“He asked her for permission to smoke and she said it was fine, but then she freaked out because she thought he did it too often during their honeymoon,” the source explains.

SPOILER ALERT: The couple split before the end of the season, not even making it to “decision day” when the show asks if they want to stay married or divorce.

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“Heather refused to put up with his smoking," the source says. “Heather and Derek’s relationship was very short lived."

For more updates on the Married at First Sight cast, pick up the latest issue of In Touch, on newsstands now!

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