The 34-year-old royal, who attended Her Majesty's funeral alongside her husband Edoardo Mapelli Mozzi, shared her grief with her sister Princess Eugenie and their parents, Prince Andrew and Sarah Ferguson, who no doubt leaned on each other for support during the emotional occasion.
WATCH: Princess Beatrice and Edoardo Mapelli Mozzi's enduring love story
Body language and relationship expert Tina Wingman spoke to HELLO! about Edoardo's "strength" on the day, commending his ability to "understand and sympathise" with his wife's grief.
How Edoardo Mapelli Mozzi supported Princess Beatrice
The royals rarely show public displays of affection, partly due to their professionalism when on duty, but also because stoicism is an unwritten rule of royal etiquette.
The royal couple held their composure at the Queen's funeral
This doesn't mean they're unaffectionate behind closed doors, however. On arrival at Westminster Abbey, Princess Beatrice and Edoardo comforted each other by holding hands, yet the couple shifted away from each other upon entrance to the Abbey.
"Edoardo helped Princess Beatrice retain her composure without physical affection," explains Tina. "He mirrored her body language and comforted her with strong eye contact whilst gauging his wife's feelings."
"He appeared to be attentive and caring from the sidelines, a pillar of strength for his wife and remaining by her side throughout. Edoardo seemed to understand and sympathise with Princess Beatrice's grief, and his presence was likely a great comfort to the Princess at this emotional time," Tina continued.
While the couple didn't show any physical affection during the service, Tina explains that their heads were sometimes angled towards each other.
Edoardo kept an attentive eye on his wife for support
"This shows their closeness and how they care for each other," says Tina, even if the action is subconscious.
"Out of all couples at the funeral service Edoardo appeared to be one of the most considerate partners, he genuinely looks heartbroken for his wife," adds Tina.
The news of Her Majesty's death was also a difficult reality for Edoardo, who took to Instagram to share a candid moment of reflection in tribute to the late monarch. "Incredibly hard to process the last 24 hours," he wrote.
Princess Beatrice was overcome with grief over her grandmother's death
"What an incredible woman and extraordinary mark she's left on the entire world. She was the rock on which modern Britain was built."
Touching upon his family, he added: "Feeling very lucky that our little ones got to spend time with her this summer. Rest in Peace, Your Majesty. We will miss you so much. Brokenhearted [broken heart emoji]."
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