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Royally kindhearted.

Duchess Kate and Prince William visited the Royal Marsden Hospital in Surrey last month, but the philanthropic acts didn't end there. Kate, 29, followed up her visit with a personal letter to young cancer patient Fabian Bate.

"This must be a troubling time for you, your parents and your sisters, but I know I left the Royal Marsden assured by how incredibly talented, kind and clever the team at the hospital are," she wrote to the 9-year-old boy, as excerpted by London's Evening Standard. "Combined with your belief and positive energy, you couldn't be in better hands." 

In Kate's note, written on St. James' Palace letterhead, Kate told Fabian, who suffers from leukemia, she was thrilled that one of his older sisters was a bone marrow match. "I will keep my fingers crossed that your health goes from strength to strength in the months ahead," she said.

Fabian's family was shocked when the letter from Kate arrived at their home address. The boy's father Darrell told the Evening Standard: "It was a very personal letter. It certainly didn't look like the standard templates these official letters so often use. It contained very specific information that she must have remembered. We were very touched as she must do a lot of this stuff and to remember Fabian is very moving."