Princess Eugenie was pictured at a Super Bowl party with Prince Harry.

While many people think it's adorable that they're hanging out together, a royal expert says it was a mistake to be photographed with the Duke of Sussex.

The Princess of York appears to be the first royal to pay him a visit since he and Meghan Markle relocated to the United States in 2020 following their retirement from prominent royal jobs.

Prince Harry and Princess Eugenie were pictured in the stands together, while Meghan Markle and Princess Eugenie's husband, Jack Brooksbank, were not present at the star-studded event.

Since their departure from the royal family in 2020, the Duke and Duchess of Sussex have maintained a frosty relationship with other royals.

Additionally, the couple spoke to Oprah Winfrey and made some incriminating accusations about their blue-blooded family, including discussions about how dark their son's complexion would be prior to Archie's birth.

However, royal researcher and biographer Duncan Larcombe reports that Princess Eugenie's public appearance with Prince Harry is apparently "breaking lines" with the rest of their family members.

"The royals have been quite constant and firm in their treatment of Harry and Meghan, as we've seen," the expert told OK magazine. By depriving Harry of his titles, the Queen has continued to effectively punish him for fleeing."

He described how Princess Eugenie is "breaking ranks" - by being publicly visible encouraging Prince Harry and Meghan Markle in their new life.

She is apparently applauding the Sussexes' remarks about the royal family, and Princess Eugenie is the only royal who has been spotted with the pair, since "no one would be caught dead anywhere near them."

"Some believe Eugenie is Harry's only chance of being reintroduced to the Royal Family if things do not work out in paradise," Larcombe continued.

"With Eugenie present, it appears as though she is the only remaining link to his family."

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Not only was Princess Eugenie the only royal to visit Prince Harry and Meghan Markle in California, but she also may have been the only member of the royal family to meet their newborn daughter, Lilibet Diana.

Lilibet was born in June and has yet to meet any members of her royal family.

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