Princess Kate may be famously close to her parents and siblings, but according to royal experts, one of the most important relationships in her life isn't with a blood relative at all.
Behind palace walls, the Princess of Wales has formed an especially close friendship with Sophie, Duchess of Edinburgh. A bond that has quietly grown over the years into one of the strongest relationships within the Royal Family.
© CAMERA PRESS/ROTARoyal commentators have even described Sophie as the older sister Kate never had, thanks to the guidance, empathy and unwavering support she has offered the future Queen.
From mentorship to true friendship:
Their close relationship reportedly began shortly after Kate joined the Royal Family.
According to royal reports, the late Queen Elizabeth II encouraged Sophie to help Kate navigate life inside the monarchy. Having married Prince Edward after growing up in a middle-class family herself, Sophie understood the unique challenges of adapting to royal life in a way few others could.
© CAMERA PRESS/ROTAWhat started as an informal mentorship has since evolved into a genuine friendship built on mutual trust and shared experiences.
Both women married into the Royal Family after lengthy courtships, giving them time to understand the realities of royal life before walking down the aisle. They also share a commitment to protecting their children from excessive public attention while balancing their royal responsibilities.
The "older sister" Kate never had
Royal biographer Ingrid Seward told our sister publication HELLO! that the pair "have a sisterly bond," adding that "Sophie is like the older sister Kate never had."
© Doug Peters"They are both protective of their children. Sophie has had a young family, so she knows what it's like trying to protect them while being in the royal world," Seward explained, describing both women as "incredibly kind girls."
She also revealed that Sophie has quietly remained part of Kate's private support network for years.
© CAMERA PRESS/ROTA"Sophie has been there in the background" for Kate, Seward said, noting that the two likely formed a close connection early because they shared similar experiences as commoners marrying into the Royal Family.
"They both had really long romances with their husbands-to-be. By the time they got married, they had more knowledge than the royal brides before them about what they were getting into."
A quiet source of strength:
The warmth between the two women has become increasingly visible during public engagements.
© Chris Jackson/WPA Pool/ShutterstockOne of the clearest examples came during the annual Remembrance Sunday service, when Sophie gently placed a reassuring hand on Kate's back as they left the balcony overlooking the Cenotaph.
The subtle gesture quickly caught the attention of royal watchers, who viewed it as a touching display of support following the Princess of Wales' return to public duties.
© Richard Pohle/WPA Pool/ShutterstockDuring Kate's recovery, Sophie and Prince Edward also took on additional royal engagements, helping ease the workload while the Princess stepped away from public life.
Royal biographer Robert Jobson also reflected on the Remembrance Day moment, telling HELLO!, "That moment said a lot. The royal family are all looking after Kate, and there is a protective bubble around her."
More than royal in-laws:
Their closeness extends beyond official engagements. Kate and Prince William live at Adelaide Cottage on the Windsor Estate, while Sophie and Prince Edward reside nearby at Bagshot Park, making it easy for the families to spend time together away from the public eye.
© CAMERA PRESS/ROTARoyal observers have also noted that the pair often share private jokes and warm interactions during events such as Garter Day, leading many to describe their relationship as less like aunt and niece by marriage and more like genuine sisters.
Their bond is also said to extend to the next generation, with Princess Charlotte reportedly enjoying a close relationship with Sophie and her daughter, Lady Louise.
© PA ImagesAs the Princess of Wales continues balancing public life with family and her gradual return to royal duties, Sophie has remained one of her most trusted allies. A steady presence whose quiet support has become one of the monarchy's strongest behind-the-scenes relationships.
