Downton Abbey star Michelle Dockery's fiancé passes away, aged 34.

Downton Abbey star Michelle Dockery has been hit with tragedy after her fiancé died aged just 34.

Dockery, who played Lady Mary Crawley on the popular TV show got engaged earlier this year to PR guru John Dineen.

Downton Abbey star Michelle Dockery is grieving the loss of her partner. Via Instagram.

She has now appealed for privacy after the 34-year old passed away in a hospice in Ireland after a long illness.

According to The Daily MailDineen is believed to have died from a “rare form of cancer.”

Michelle Dockery and her partner John Dineen. Via Getty.

The couple were introduced by Alan Leech, who is also an actor on the show.

In 2014 the notoriously private actress spoke of her relationship  saying: “I have a wonderful man in my life from Ireland. We were introduced by Allen Leech. That’s all you need to know.”

She flew back from the US to be with him as he passed away.

A spokesperson for Dockery – who turned 34 today – told ITV News: “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 his family and with all affected by cancer.