If you know the White family in Booterstown, Dublin, you had better watch your Ps and Qs because they have connections to the British royal family.
That's according to researchers at the National University of Ireland Maynooth, who only made the discovery in recent days.
It came about as they started to examine an artefact last November – known as the Morpeth Roll – which measures 420 metres (1,378 feet) and is three times the length of Croke Park, that's the stadium, not the agreement or its extension.
The reason it is so long is because it contains the signatures of more than 160,000 Irish people paying tribute to George Howard, or Lord Viscount Morpeth, when he left his post as chief secretary of Ireland in 1841.
Genealogists found Henry White, from Booterstown, south Dublin, who is a distant “rags to riches” Irish cousin of Prince William. The connection? Mr White’s great-grandson Luke Henry White married Lavinia Spencer, sister to Princess Diana’s grandfather Albert Spencer, in 1919.
Deirdre Watters, of National University of Ireland Maynooth, said: “Henry’s father Luke White appears to have made his money in publishing companies.
“We think his is a bit of a rags to riches story. They would have been nouveau riche at the time.”
As they rose to prominence the Whites bought Luttrellstown Castle, on the edge of Phoenix Park, where David and Victoria Beckham got married.
Well-known figures who signed the roll include Irish political leader and emancipator Daniel O’Connell, entrepreneur and transport pioneer Charles Bianconi as well as Irish nationalists Thomas Davis and Charles Gavan Duffy.
For years the Morpeth Roll remained hidden away in a basement at Castle Howard in Yorkshire – the ancestral home of Lord Viscount Morpeth.
It will be on view to the public for the first time in 170 years as it is taken on a 14-month tour of Ireland to coincide with its online release.