As parents across the country took to social media to show off their own little ones dressed for their big day this week, the royal joined in with a snap of her and older sister Beatrice.
The royal siblings are pictured wearing their Upton House school uniform of navy dresses, blue blazers and matching boater hats in the early 1990s.
While Eugenie looks noticeably excited, proudly grinning with her little red backpack, Beatrice looks less so.
She captioned the sweet photo: “Throwback to school days. Clearly I was more excited than Beatrice!”
The bride-to-be, who will marry boyfriend Jack Brooksbank on October 12, joined Instagram in March and has shared many photos from her childhood on her public social media profile.
Her last post before the school picture paid tribute to her sister Beatrice on her 30th birthday in August.
She also keeps her followers up-to-date with her charity work and initiatives.
The princesses gave their first joint interview in the September issue of British Vogue, where they revealed more about royal life and their close bond.
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