To mark the momentous day, Sarah 'Fergie' Ferguson shared a throwback photo from her youth to Instagram, featuring her dearly departed mother, Susan, and her sister, Jane.
"Happy Mother’s Day to my dearest Mum, who died so young at 61, to my dearest sister Jane (a superb mother) and to my girlies who are amazing mothers..," the Duchess of York wrote.
In a second slide, Fergie shared a photo of her youngest daughter, Eugenie, as a child sitting atop a horse while her proud mum cuddled her little one.
Along with her mum, Princess Eugenie also marked Mother's Day on her own Instagram.
Sharing a sweet moment of the new mum hugging her only son August, along with a stunning portrait of Fergie as well, the mother penned her well wishes for the day.
"Happy Mother's Day to every mother out there. 🌼💐🌸🌹🌻🥀🌺🌷," Eugenie wrote.
The Yorks weren't the only ones to celebrate, with Prince Charles and Camilla Parker-Bowles equally delighting in the opportunity to pay homage to their maternal influences.
Sharing photos of Prince Charles and his mother, The Queen, as well as a vintage portrait of Camilla with her late mother, Rosalind, the royals paid tribute on the bittersweet day.