Autumn Kelly, the fiancee of Queen Elizabeth's eldest grandson, Peter Phillips, has renounced her Catholic faith so her future husband will not lose his place in the royal line of succession.
Ms Kelly, 31, a Canadian, was accepted into the Church of England before the couple's wedding on May 17, the Times Online reports.
The 1701 Act of Settlement which bars monarchs and their heirs from becoming or marrying Catholics, would have forced Mr Phillips to surrender his place in line if Ms Kelly had not converted. Mr Phillips, 30, is currently eleventh in line to the throne and is to become the Queen's first married grandchild.
A Buckingham Palace source told the UK Daily Telegraph: "she was not asked to do this; she did it of her own accord."
Ms Kelly a management consultant from Canada, met Mr Phillips at the Canadian Grand Prix in Montreal in 2003 and moved to the UK to be with him shortly afterwards. Their engagement was announced last July.
The couple live together in a cottage in Gatcombe Park, the Gloucestershire estate owned by his mother, the Princess Royal.
Ms Kelly's parents are reported to be thrilled at their daughter's engagement. "I've met him a few times and he's a great guy, a really nice person," her mother, Kathleen, said.
"Autumn is a very serious and intelligent young woman. She may be young, but she knows the world. And he's a great guy. Isn't that what counts?" she said.
Mr Phillips does not have a royal title and works for the Royal Bank of Scotland while Ms Kelly now works for an American computer distributor.
It is not known if Ms Kelly was a practising Catholic but she was educated at Catholic schools, the paper says.
The wedding will take place at St George's Chapel in Windsor.
Fiancée secures royal succession by abandoning her Catholic faith (Times Online, 1/5/08)
Prince Peter Phillips
Why Autumn had to renounce her faith (Times Online, 2/8/07)