Michelle Dockery's boyfriend, John Dineed, has died. Credit: David M.Benett/Centrepoint/Getty Images for Centrepoint

Tragic. Downton Abbey star Michelle Dockery's partner, John Dineen, has passed away at the age of 34 after battling a rare form of cancer.

Dineen, a PR professional from Ireland, died at a hospice in Cork on Sunday, December 13, just two days before the actress' 34th birthday, a spokesperson for Dockery confirmed to Britain's ITV News.

Dineen had been working in London but had returned to Ireland earlier this year to spend time with his parents after his devastating cancer diagnosis.

According to the Irish Independent, Dockery, who played the role of Lady Mary in the hit British TV series Downton Abbey, had flown back to Ireland from America to support him, and was with him at Cork's Marymount Hospice when he passed away.

"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," Dockery's spokesperson told ITV News in a statement.

Dockery had been mainly tight-lipped about her relationship with Dineen, who she had been dating since 2013 after an introduction from Downton costar Allen Leech.

"I have a wonderful man in my life from Ireland. We were introduced by Allen Leech. That's all you need to know," she told a publication in 2014. There were unconfirmed reports earlier this year that the pair were engaged to be married.

Dockery has kept her grief to herself in recent weeks. Just days before her partner's death, she appeared on Watch What Happens Live with Andy Cohen and gave no hint of her personal anguish as she laughed on screen alongside her and Dineen's mutual friend Leech.

A private funeral is expected to take place in Cork on Wednesday, December 16.

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