Kate Middleton once shared a story about how her father once made a blunder that left her humiliated during Wimbledon 2017.

The Duchess of Cambridge said it happened while she watched the tennis match with her parents, Michael and Carole Middleton. They had reportedly just watched tennis ace Pete Sampras play and as they were walking away from their seats, they saw British player Tim Henman.

The 40-year-old recalled how her father mistakenly called the player by the wrong name. As they walked past him, he cooly called him "Pete."

"My father is not going to appreciate this, but we were walking past Tim Henman and we had just seen Sampras play. My dad said very coolly: 'Hi Pete'. I was mortified!" Kate Middleton told the BBC in 2017 for the documentary called "Our Wimbledon."

However, the embarrassing experience did not stop the Middletons from returning to Wimbledon afterward. Just recently, the Duchess of Cambridge joined Prince William in the stands as they watched the games on Tuesday.

They were seated apart from Michael and Carole Middleton, but the duchess made sure to acknowledge her parents' presence when she blew them a kiss from her seat.

According to OK! magazine, Carole even stuck her tongue out at her daughter and Prince William which left them in stitches. The moment was caught on video and shared online for the public to admire the playful banter.

Kate Middleton is a big tennis fan. She is even patron of the All England Lawn Tennis and Croquet Club. Queen Elizabeth II passed down the role to her in 2016 after she held the title for over six decades.

The mum-of-three wore a blue polka dot dress and adorned it with a small green and purple ribbon on her chest to signify her role. At one point, she engaged in small conversations with comedian David Williams and his mum, Kathleen, who were seated behind her and Prince William.

Kate Middleton's parents, on the other hand, also enjoyed themselves. Carole was spotted sipping on a drink when she stuck her tongue out at her daughter and at Prince William.

Kate Middleton
The Duchess of Cambridge at Wimbledon AFP / Getty Images