On the job as an air ambulance pilot recently, William blew up a surgical glove to create a "puppet" for 3-year-old Luke Sawyer, who was having an allergic reaction.
William was called to the scene after Luke – who is only a few months older than William's son Prince George – suffered the reaction at St. Joseph's Catholic Primary school about 40 miles north of London.
While doctors worked to help Luke, he was given the inflated surgical glove from pilot William, who had tied two of its fingers as ears and used a pen to decorate it with eyes and a mouth.
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"We thought it was a really touching thing for Prince William to do, as it really took his mind off everything that was going on," Luke's mom, Donna, told The Telegraph.
William "works really hard and went beyond the call of duty to put Luke at ease," she added. "Luke wouldn't let go of the balloon glove, even taking it to bed with him."
Last month, William's bosses at East Anglian Air Ambulance defended him over accusations he was not doing many shifts.
William works up 80 hours a month as he balances that air ambulance shifts with his royal duties.