Kate Middleton's subtle gestures at Wimbledon suggest she is not 'on top form' amid cancer battle

Kate Middleton looked 'relaxed and elegant' at Wimbledon, despite displaying minor signs of not being completely 'on top form,' according to a body language expert, as reported by Daily Record.

The 42-year-old Princess of Wales made a rare public appearance today at the tennis championship, where she was accompanied by her daughter, Princess Charlotte, and her sister, Pippa Middleton, to present the winner's trophy at the men's final.

Fans were delighted to see Kate, as this was only her second public appearance since disclosing her heartbreaking cancer diagnosis in March.

Kate was previously seen at the Trooping the Colour, the King's annual birthday celebration, last month, where she appeared cheerful alongside her husband, Prince William, and their three children, the Mirror reports.

It was announced on Saturday that the Princess would unexpectedly return to Centre Court, as she is a keen tennis enthusiast and regular Wimbledon attendee.

Arriving at 1:45 pm, Kate radiated happiness as she waved twice to the adoring crowds, the Mirror reports.

Commenting on her emotional comeback, body language expert Judi James told the Mirror: "Kate oozed regal confidence here, greeting the screaming fans from the walkway with a delighted and slightly surprised-looking wave that Charlotte mirrored once her mother had turned to nudge her."

Wearing a deep purple outfit, often associated with royalty, Kate appeared relaxed and elegant.

Her prolonged conversations with people backstage indicated she wasn't eager to return to the comfort of her seat.