This is tragic.

John Dineen — the fiancé of Downtown Abbey star Michelle Dockerydied on Dec. 13 after succumbing to cancer, which he was diagnosed with earlier this year. He was 34-years-old.

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michelle dockery jon dineen

Michelle, 34, cancelled promotional appearances she had scheduled in the US and flew to Ireland last Thursday to spend John's final days with him.

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The pair began dating in 2013 after one of her costars introduced them. Back in May, it was reported that he asked for her hand in marriage.

The actress has yet to comment on John's passing, though a spokesperson for Michelle told the Irish Independent, "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."

Our thoughts are with John's loved ones during this difficult time.