Kate Middleton has 'crazy' hobby she does in the dark - but William thinks she's mad

Kate Middleton has a little-known hobby that she enjoys in the dark which Prince William has branded her 'crazy' for.

The Princess of Wales, who is currently undergoing chemotherapy following a cancer diagnosis, previously opened up about her intriguing hobby during an appearance on Mike Tindall's podcast, The Good, The Bad and The Rugby.

The mum-of-three expressed her passion for sports, highlighting one particular activity that William deems her 'crazy' for as he doesn't understand her love for the unusual past time.

Despite William's disapproving opinion on his wife's adventurous hobby, Kate confessed she 'loves' it so much that she's willing to do it in the dark and cold, OK! reports.

She told Mike, who has been married to Zara Tindall since 2011: "I can always remember being physical, using our bodies, whether it's walking, climbing the Lake District, in Scotland [or] swimming from a young age.

"[My parents] always encouraged us to be physically active and sporty, and they always encouraged us into doing team sports and trying things."

She then revealed her love for cold water swimming which sees Kate take a brisk dip in the great outdoors.

Kate gushed: "Cold swimming - the colder, the better. I absolutely love it. Slightly to the point where William's [saying] 'You're crazy' and it's dark and it's raining. I will go and seek out cold water. I love it."

The 42-year-old has also earned her stripes as a diver, boasting a Professional Association of Diving Instructors (PADI) Advanced Open Water Diver qualification which allows her to explore the underwater world down to 98 feet (30 metres).

Her husband, Prince William, shares this underwater enthusiasm and has been a qualified scuba diver for quite some time. He also serves as the president of the British Sub-Aqua Club.

A Royal spokesperson told the Telegraph: "Diving is something Kate very much enjoys, and William who is of course president of the BSAC, has said in the past that he is hopeful his children will become interested in the sport."

To secure this prestigious diving certification, the future Queen had to successfully complete five different dives, which included mastering deep diving and underwater navigation.

The course not only equips divers with the skills to manage the physiological challenges of deep-sea exploration but also trains them in using essential gear such as compasses and dive knives, crucial for emergency situations like entanglement in fishing nets.

In March, Kate released a video statement revealing the "huge shock" of her cancer diagnosis as she told the public: "Tests after the operation found cancer had been present.

"My medical team therefore advised that I should undergo a course of preventive chemotherapy and I am now in the early stages of that treatment".

Despite her upsetting news, she conveyed an uplifting message as she assured the public: "I am well and getting stronger every day."

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