Sarah Ferguson left Prince Andrew out of her special family tribute, which featured a new picture of Beatrice and Eugenie.
The Duchess of York, who has 698,000 Instagram followers, posted two new photographs to mark Father's Day. The first picture showed Princesses Beatrice and Eugenie as young children with their late maternal grandfather, Major Ronald Ferguson, who died in 2003.
Sarah's second photograph was a solo shot of her late father when he was much younger.
The Duchess of York captioned the post: "Happy Father’s Day Dearest Dads."
However, the Duke of York, Sarah's ex-husband, was not included in either of the pictures, despite him being the father of her two daughters.
Sarah and Andrew's 10-year marriage ended in divorce in 1996, but the two have maintained a good friendship, with the Duchess even living at Royal Lodge, the Duke's home since 2003.
During a promotional event for a children’s book in 2013, Fergie was asked if she and Andrew would remarry.
She said: “He’s still my handsome prince, he’ll always be my handsome prince. It’s lovely that we are such a family and the story has a happy ending all the time.”
Speaking in 2000 to Tatler, Andrew explained his unusual living situation with his ex-wife.
He said: "We are not just doing it for the children. We are doing it for our own benefit too.
"I don’t rule remarriage out and I certainly don’t rule it in. If ever the opportunity arose, I do not know what I would do, as it is not in the plan."
Sarah joined the Royal Family at St Mary Magdalene Church for the traditional Christmas Day service on the Norfolk estate last year, the first time since 1991.
In a post on Instagram on Boxing Day, the duchess wrote that she was "feeling grateful" to be included in the festivities.
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