"He likes dinosaurs. Do you like dinosaurs, Charlie?"
During his visit, Prince William met with several other patients and staff members, including 11-year-old Zak Gillard, who was just diagnosed with a rare brain tumor, 6-year-old leukemia patient Sebastian Gamble-Banas and 3-year-old leukemia patient Charlie Miller.
The youngster beamed at the father-of-two, Prince George and Princess Charlotte, as he put a name tag around her wrist and nods her head when he asks: "Is it alright?"
Zak's mum, Stephanie Gillard, said: "He said George was noisy and charging around the place". "Sebastian, when people are talking to you, what do you do?" his mother, Sara asked. "He's engrossed", laughed William.
Prince William marked the 10th anniversary of becoming president of the Royal Marsden, a position previously held by Princess Diana, by helping out in a children's unit and in radiotherapy at the hospital in Sutton, Surrey. "He's too old for me to marry", said Princess-obsessed Daisy, from Kingston, Surrey, who enjoyed being cared for by the future King.
He was reunited with radiotherapy worker Fiona Bragg, 55, who took William under her wing when he spent a day shadowing staff at the south London hospital in 2005, two years before he became president of the Royal Marsden.
The hospital has an worldwide reputation for ground-breaking research and pioneering treatments and technologies, and the prince kicked off his visit in the radiotherapy department, where he spoke with clinicians about the U.K.'s first MR Linac, a state-of-the-art machine set to make radiotherapy more effective and reduce side effects for cancer patients.
She recalled how she spent more than an hour showing the Duke how to check patients in, once they had arrived at reception.
Meeting her again today, William, laughing, said: "It's a long time ago. I really enjoyed myself", William said.
The Duke will soon finish his part-time role as an air ambulance pilot for East Anglian Air Ambulance.
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