Prince William told a Wrexham youngster of his childhood experience in hospital as he unveiled a state-of-the-art scanner.
The Prince met brain tumour patient Sion Meredith, seven, of Acton, during a visit to Liverpool's Alder Hey Children's Hospital yesterday (Monday, February 22).
He was at the hospital to open a new intra-operative 3-T MRI scanner, the first in Europe for children.
He told Sion he was scared when he had an MRI scan aged eight and said: "You are a very brave boy."
The new scanner was bought after a £3 million donation to the hospital's charity, the Imagine Appeal, by the Barclay Foundation.
William said he sympathised with Sion, who was frightened and restless when he went in the noisy scanner for the first time in January last year.
The youngster wore a Wales rugby shirt as he chatted to the Prince about football, rugby and time off school.
Sion was diagnosed with a common childhood brain tumour in January 2009. It was successfully removed in December using the new intra-operative theatre suite at Alder Hey.
The Prince was given a tour of the operating theatre by Conor Mallucci, a consultant paediatric neurosurgeon at Alder Hey.
Speaking after he showed William the new equipment, Mr Mallucci said the scanner was "a huge benefit".
He explained why there had been difficulties in scanning patients during surgery in the past.
"The problem has been MRI scanners don't like metal - they are huge magnets - and so it's taken years to develop a system where you can safely have theatres and MRI scanners together.
"This is the culmination of years of research to try and get the right combination."
There are similar scanners for adults in the UK, but this is the first exclusively for children.