Meghan Markle Divorced Trevor Engelson After Affair With 'Suits' Costar, Claims Sister In Bombshell Book

Meghan Markle and first husband Trevor Engelson may have parted ways after the actress had an affair with one of her Suits costars, claims the Duchess' half-sister Samantha according to a world-exclusive report in The Royal Observer. 

The Royal Observer was the first to obtain a copy of Samantha's new tell-all The Diary of Princess Pushy's Sister: A Memoir, in which she writes: "We heard through the grapevine that Meg was involved with someone on the show."

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According to The Royal Observer, Samantha says she was devastated, especially for their grandmother who was a big fan of Trevor, a film producer. "I was in shock because I thought they had a marriage that defied all odds in Hollywood," writes Samantha.

It seems that Meghan, 39, may not have been the only one stepping out, however, as The Royal Observer also reported that Samantha claims Trevor was in the throes of a new relationship — with Meghan's best friend. "It takes two to tango," she notes.

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"We didn't really talk about her marital problems and I wish that we could have because I had been through it and felt I could be an experienced source of comfort, and maybe advice," writes Samantha, according to Royal Observer.

The Duchess of Sussex and Engelson got married in 2011 in Ocho Rios, Jamaica, after a seven-year-long courtship. But the relationship didn't last much longer – they split in 2013, citing "irreconcilable differences."

The controversial 328-page book, The Diary of Princess Pushy's Sister: A Memoir, is expected to be released later this week.