As the Duchess of Cambridge went into labour this morning, professional genealogist Anthony Adolph revealed the princess's connections to the county.
The family tree expert said her great-great grandfather Gavin Fullarton Robison was a bank clerk who died in Canterbury's Old Dover Road in 1925 and his daughter Constance married Frederick George Glassborow, a bank manager who died in Earls Avenue, Folkestone in 1954.
Constance and Frederick's daughter Valerie Glassborow went on to marry Peter Middleton.
Valerie and Peter's son Michael Middleton is Kate's father.
Frederick's father, also called Frederick Glassborow, was a shipping manager who died in Lismore Road, Beltinge, in 1932.
Mr Adolph, who is the princess's 11th cousin once removed, said: "Having Kate as its mother makes the new royal baby unusually interesting because half of his or her genes will come from completely ordinary English families.
"The baby has masses of royal blood through its father, but through Kate he or she is descended from and related to coal miners, lorry drivers and builder's labourers.
"The royal child will be truly representative of the people he or she will one day rule.
"There are plenty of Robisons and Glassborows in the Kent telephone directories, so masses of people in the county are likely to have close family ties to the new royal baby."
Prince William and Kate Middleton on their wedding day. Picture - John Stillwell
Mr Adolph, the author of The King's Henchman, trained at The Institute of Heraldic and Genealogical Studies in Canterbury and worked as a genealogist in the city for 14 years.
It was while there he discovered his distant connection to the future queen.
He said: "I traced my grandmother's Fairfax ancestry.
Professional genealogist Anthony Adolph
"I didn't think they were very exciting at the time, but later I found that Kate is descended from exactly the same family.
"It means she is my 11th cousin once removed and the royal baby, our future king or queen, is my 11th cousin twice removed.
"It just goes to show that when you start tracing your family tree you never know what you'll find.
"You might even discover that you are the cousin of a king or queen."
The Duchess of Cambridge is in labour at St Mary's Hospital, in Paddington, after being admitted to the Lindo Wing at just before 6am.
Kate travelled from Kensington Palace by car with William at her side and without a police escort.
The announcement of the birth of the third in line to the throne will follow tradition with a notice placed on an easel outside Buckingham Palace.