Many royal fans took to social media to comment on how "glamorous" and "beautiful" Kate's mum looked.

One royal fan posted on X: "The Princess of Wales's mother, Carole Middleton, attends #Wimbledon day four today.

"Oh my, the #LionessofMiddleton looks beautiful and Princess Catherine has her mum’s smile.

Another said: "Loving Carole’s outfit and new haircut."

This is the second public appearance the Middletons have made recently.

Last month, they drove royal fans into a frenzy when they made a surprise appearance at Royal Ascot and were seen chatting to their son-in-law, Prince William.

Meanwhile, the Princess of Wales, who is an avid tennis fan, has been absent most of the year after having been diagnosed with a form of cancer but made her triumphant return last month, when she attended Trooping the Colour in London.

Kate is currently undergoing preventative chemotherapy and in her latest message, she said the treatment is ongoing and will be for the next few months.

Her mother Carole is said to have been a pillar of strength to her daughter, rallying around her family and helping her through her treatment.