The two women endured a complicated relationship but in her first interview in almost 20 years The Duchess Of York has revealed her true feelings about Diana.
She said: "I thought of absent friends and family; of Diana — but she's with me all the time. What I miss most is her tinkling laughter.
"Diana was my best friend and the funniest person I knew.
"She had such timing and wit. It was a total joy to be with her because we just laughed and enjoyed life so much, and I know she would have loved the wedding."
Fergie was photographer beside her former husband Prince Andrewat the wedding when their daughter exchanged vows with Jack Brooksbank on October 12 in Great Britain.
And this sparked many Royal observers to speculate that the couple could get back together again.
But that scenario seems unlikely.
Fergie, 60, revealed: "I'm not divorced from Andrew – I'm divorced to him.
"We both say it. We are completely compatible. Our bywords are communication, compromise and compassion.
"July 23, 1986 was the happiest day of my life. Andrew is the best man I know. What he does for Britain is incredible; no one knows how hard he works for his country.
"My duty is to him. I am so proud of him. I stand by him and always will. The way we are is our fairy tale.
"Although we are not a couple, we really believe in each other. The Yorks are a united family. We've shown it. You saw it at the wedding.
"We stand up for each other, fight for each other. We're totally respectful of each other's position and thoughts and we listen to each other. Our children listen to us, too."
Ferguson has publicly defended her former husband and now seems to be back in the graces of the Queen and the other royals.
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