Kate Middleton Blows a Kiss from the Royal Box at Wimbledon — Just Like She Did Last Year

The recipient of the Princess of Wales' air kiss remains a mystery

Kate Middleton showed love to someone in the stands in a blink-and-you'll-miss-it moment at Wimbledon!

On Sunday, cameras caught the Princess of Wales blowing a kiss from her front-row spot in the Royal Box at the Grand Slam tennis championship.

The recipient of the sweet signal remains a mystery. It wasn’t directed at her immediate family, as Prince William, Prince George and Princess Charlotte sat beside her.

RELATED: Prince George and Princess Charlotte Watched Wimbledon in the Royal Box, but Kids Usually Aren't Allowed

The Princess of Wales’ kiss called back to a similar gesture last year when she blew a kiss to her parents, Carole and Michael Middleton. Although they were all seated in the Royal Box, Kate wasn't next to her mom and dad, so she warmly waved after taking her seat beside her husband at the tennis tournament.

Though Carole and Michael didn’t seem to watch Wimbledon at the All England Lawn Tennis and Croquet Club (of which Kate serves as patron) this year, the couple's other two kids did. Princess Kate’s brother, James Middleton, and his wife, Alizee, attended on July 6, the day after announcing Alizee is pregnant. The baby on the way is the couple's first child, and James said they will “end the year with the most precious little addition to our growing family."

Meanwhile, Kate’s sporty sister, Pippa, and her husband, James Matthews, checked out the tennis matches together on July 12.

Prince William and Princess Kate, both 41, attend the Wimbledon finals together most years and brought their two eldest children to the thrilling men’s singles final on Sunday. George, 9, went for the first time last year and Charlotte, 8, had her debut day at the finals — as Kate revealed that 5-year-old Prince Louis, 5, was sad he didn't tag along!

According to Ella Ottway, who runs youth programs at All England Lawn Tennis and Croquet Club, the Princess of Wales said, “ ’Louis was very upset he wasn't coming today,’ ” PA News reported.

"It's Charlotte's first time, George came last year. They've been eagerly watching," Kate explained of her two eldest children.

RELATED: Prince George and Princess Charlotte's Cutest Wimbledon Moments — and Most Animated Reactions!

In another adorable anecdote, a 16-year-old Wimbledon ball boy named Joel said that Princess Kate revealed that Louis “tries to practice the standing and staying serious like us,” PA News reported. “He tries to practice the stands and how we stand at the back of the court and next to the players,” Joel explained.

Little Louis might have to wait a little longer before he gets to watch tennis from the Royal Box, as his older brother and sister both went for the first time at age 8. While George and Charlotte were on their best behavior in the exclusive enclosure over the weekend, Wimbledon has had a tricky history regarding kids in the Royal Box.

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In September 1999, The Guardian reported that Katharine, Duchess of Kent hoped to invite two young family friends to sit with her in Royal Box at Wimbledon on different days. While the Duchess of Kent’s 10-year-old godson was approved to join her, organizers said they couldn’t accommodate the 12-year-old son of the Duchess' bereaved friend in prime space. John Curry, who then served as chairman of the All England Lawn Tennis and Croquet Club, apologized but stuck to policy, explaining that only royal kids were allowed to sit there.

"As happens every year with all our royal guests, I reconfirmed our guidelines concerning the invitation of additional guests and the subject of children. No royal has been limited to one guest in the past or will be in the future,” Curry said in a statement at the time.

"Because of demand for space in the royal box, we also ask that, apart from children of the royal family, children are not invited as they exclude other worthy people from attending, many of whom contribute to tennis," he added.

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