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Michelle Dockery is in mourning.

The "Downton Abbey" actress is grieving the loss of her fiancé, John Dineen, who died at Marymount Hospital in Cork, Ireland, Sunday at age 34. He is said to have suffered a long-term illness.

In a statement, Dockery's rep said, "The family is very grateful for the support and kindness they have received but would kindly request that they are left to grieve in private." Per reports, a funeral service is expected to take place in Cork Wednesday.

Dockery reportedly flew to Ireland from the United States to be with Dineen and his family in his final hours. She had been promoting the upcoming final season of the hit series with her co-stars, making television appearances on CBS' "The Late Show With Stephen Colbert" and Bravo's "Watch What Happens Live." Dockery did not appear in the cast's latest photo, taken by Allen Leech outside the White House on Dec. 11.

Dineen was a senior director with FTI Consulting. It's been reported that he proposed to Dockery in February, though she never publicly announced their plans to marry. She's rarely spoken of Dineen in interviews, but in 2014, she admitted she was seeing a "wonderful man" from Ireland. "We were introduced by Allen Leech," she said. "That's all you need to know." Leech introduced Dockery and Dineen in 2013.

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In an interview with the Red, published this month, Dockery briefly mentioned her fiancé. "When 'Downton' first became…[successful]...I was so overwhelmed and found it hard to adjust to being recognized and having my private life in the spotlight. You quickly realize that the press can get to you. I've got people around me who I can turn to for advice: my mum, and my partner, John," said the star, who plays Lady Mary. "But, at this stage, my instincts are pretty good."

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