Lady Gabriella Windsor announced her engagement to Thomas Kingston last September after dating for years.
The couple is due to be married in a ceremony in St George's Chapel, Windsor Castle, Saturday – the third royal wedding on the premises within a year.
Here are some details about the happy couple in front of their big day.
Lady Gabriella Windsor
The daughter of Prince Michael of Kent, a lesser royal who is the Queen's cousin, Lady Gabriella Marina Alexandra Ophelia Windsor was born on April 23, 1981. Her mother, Princess Michael, has made headlines over the years for her incredible comments called " Princess Pushy "by the press.
Her parents married in 1978, and she has an older sibling, her brother Lord Frederick, known as Freddie, who hit the headlines after admitting to using drugs at the university.
Lord Frederick married Peep Show actress Sophie Winkleman in 2009 and the couple have two children together.
Lady Gabriella, known as Ella, studied at both Brown University in the US and Oxford University, with degrees in Comparative Literature and Social Anthropology.
The 38-year-old works as art and travel director for the branding brand Branding Latin America, based in Knightsbridge, London.
Not a "working royal", she is also the director of Playing for Change Foundation, a non-profit organization that aims to improve education through music.
Prior to her current relationship, Lady Gabriella dated the journalist Aatish Taseer, who wrote a narrative-all Vanity Fair article earlier this year claiming that they were swimming naked in the Buckingham Palace pool.
She had been with Mr Kingston for a number of years when he suggested while on the island of Sark last summer.
The groom, 40, is the director of Devonport Capital, which specializes in providing finance to businesses in "border economies".
Bristol University students worked in Baghdad, Iraq, according to the Telegraph, who is working to release hostages after joining the Ministry of Foreign Affairs diplomatic missions.
His financial career information includes roles at Voltan Capital Management and IDC Securities.
Sir. Kingston is a close friend of Pippa Middleton – the Duchess of Cambridge's sister – with the couple looking out on several occasions.
He attended his wedding to James Matthews in May 2017, accompanied by Lady Gabriella.