Despite Sarah Ferguson and the late Princess Diana once having a strong friendship – having been friends long before they were in the royal family – a comment made by Ferguson is believed to have caused a major hurdle in their friendship before Diana died.

In fact, at the time of Diana’s death in 1997, the pair hadn’t been speaking at all.

In Sarah’s autobiography, Finding Sarah: A Duchess’s Journey to Find Herself, she explained: “Sadly, 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, it stuck there for a while.

“I wrote letters, thinking whatever happened didn’t matter, let’s sort it out. And I knew she’d come back. In fact, the day before she died she rang a friend of mine and said, ‘Where’s that Red? I want to talk to her.’

“In any sibling relationship, there are ups and downs and peaks and troughs, but we were always steadfast in our friendship. We never let the sun go down on too many heated discussions. Our bond was never broken.”

Despite explaining she didn’t know the reason for the falling out, journalist and royal commentator Tina Brown has revealed that the answer lay in Diana’s shoes.

In a line published in her earlier biography, My Story: Sarah, the Duchess of York, which was published in 1996, Sarah made a comment about some shoes she had borrowed from the Princess of Wales.

Apparently, Diana didn’t take it very well.

The line read: “When I lived in Clapham, Diana helped me by giving me all her shoes (and, less happily, her plantar warts) – we wore the same size.”

Brown called the sentence ‘fatal’, writing in The Diana Chronicles: “The divorced Duchess had cashed in with an anodyne memoir, which was full of nice comments about her sister-in-law – except for one fatal line.

“She wrote that when she borrowed a pair of Diana’s shoes she had caught a verruca from them. Goddesses don’t get warts.

“Despite Fergie’s pleading apologies, Diana never spoke to her again.”

More recently, Sarah has said that her ‘heart is always with Diana’, gushing about the happy memories they both shared.

“I think about her most days because she’s the only other person who knew and was around at that time in the 80s, when we all wore those very strange clothes,” she told HELLO! in 2021.

“She was in the family before me and we had such fun.”