Prince William sparks speculation following Kate's nod to Princess Diana

Kate chose to debut a pair of Cartier Trinity hoop earrings worth £3,000 during her visit to the South Kensington hospital, where she had undergone her preventative chemotherapy treatment in 2024.

Tatler reported that the choice of jewellery could potentially be a birthday gift from Prince William, following his touching social media tribute praising her "remarkable strength" and role as "the most incredible wife and mother."

The princess was wrapped up in a Blaze Milano winter coat and a Gabriela Hearst jumper, accessorising with a Morgan small handbag by Asprey and the new hoops featuring three intertwined bands in white, yellow and rose gold.

The iconic Trinity collection by Cartier celebrated its centenary last year, boasting an impressive list of celebrity admirers throughout its history.

Grace Kelly and Romy Schneider were known for their love of the classic Trinity ring, while actress Jacqueline Bisset frequently wore a chunky bracelet from the range.

The design's origins are steeped in mystery, with some pointing to ancient Celtic roots while others trace it to Russian wedding rings.

The three interlocking bands carry deep symbolism, representing various trinities such as past, present and future, as well as love, loyalty and friendship.

The choice of Trinity jewellery carries particular poignancy as a connection to Princess Diana, who was known to wear a Trinity ring on her little finger.

The symbolism of Kate's new Trinity hoops appears particularly meaningful following her challenging year of treatment. The three intertwined bands of different metals, uniting as one piece, may mirror the princess's journey through treatment to recovery.

As she steps into her new role as joint patron, the Trinity hoops could serve as a powerful symbol of her connection to both the hospital's legacy and her mother-in-law's enduring influence.

Kate has demonstrated her own affinity for the collection over the years, wearing a chunky Trinity necklace at the National Portrait Gallery in 2012 and again in New York in 2014.

She also owns matching glittering earrings, which she wore at a SportsAid banquet at Kensington Palace in 2016.

The princess further expanded her Trinity collection with a more subtle set, including a small necklace and diamond-set studs, first spotted during a 2017 Paris visit.

During her visit, Kate spoke candidly about her experience at the hospital, saying: "I was just saying, coming in the front entrance here, having made so many quiet, private visits, actually it's quite nice."

The princess later announced her remission on social media, expressing gratitude to those who supported her and William through the adjustment to their "new normal."

In a significant development, Kate has been named joint patron of the Royal Marsden Hospital alongside Prince William, who has served as President since 2007.

The princess offered support to fellow patients and personally thanked staff members for their exceptional care during her cancer journey.