They later became related by marriage, married to two royal princess of the United Kingdom.
Fergie married Prince Andrew in 1986 in a lavish ceremony at Westminster Abbey, London.
Diana married Charles a few years earlier, in July 1981.
The Princess of Wales as to thank for Fergie and Andrew’s relationship.
Diana invited Fergie to a party at Windsor Castle held after the Ascot Races in 1985.
Both Sarah and Diana have links to the royal blood line via their ancestors.
They are both descended from William Cavendish Forth Duke of Devonshire.
He was the father of William Cavendish, Fifth Duke of Devonshire, the man portrayed in Keira Knightly film The Duchess.
He was also MP for Derbyshire in 1741 and 1747.
This also makes the very distant cousins of their husbands, Charles and Andrew.
Their children, Prince William, 36, and Prince Harry, 33, and Princess Beatrice, 29, and Princess Eugenie, 28, are first cousins.
However, Fergie revealed she did not talk to Diana for a year before she tragically died.
She told Harper’s Bazaar: “And the saddest thing, at the end, we hadn’t spoken for a year, though I never knew the reason, except that once Diana got something in her head….
“I tried, wrote letters, thinking whatever happened didn’t matter, let’s sort it out.”
Sarah Ferguson’s wedding tiara was a gift from the Queen.
However, the last time the tiara was seen in public was well over a decade ago at the White Tie and Tiara Ball hosted by Sir Elton John at his Windsor mansion on 5 July, 2001.
It seems a shame for such a tiara to have not had a public outing in years.
So what has happened to the York tiara?
As this is private gift it is likely that Sarah still has the piece.