But, in a lighter moment, he was given a birthday card to pass on to his wife, the Duchess of Cambridge, who turned 37 on Wednesday.
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Prince William gave a talk at the launch in September.
The Duke and Duchess of Sussex first appearance of the year will be on January 14. "The Duchess undertakes royal duties in support of The Queen, both in the United Kingdom and overseas - and devotes her time to supporting charitable causes and organisations, several of which are centred around providing children with the best possible start in life".
The visit, at the Royal London Hospital, Whitechapel, will be his first official engagement of 2019.
Middleton turns 37 on January 9, but if you rewind the clock about seven years, you'll recall that she got a special b-day gift courtesy (kourtesy?) of Kim K.
Google Home upgrade: Your smart speaker is set for a colossal improvement
What's more, the Assistant will even auto-punctuate your messages now, so you don't have to dictate punctuation marks as well. While the platform will no doubt arrive on much more kit this year, we now know that will include some Sonos speakers.
Kensington Palace thanked the public for their "lovely messages". According to the royal expert, the duchess looked different.
"As Patron of the 30th Anniversary Campaign, the duke will champion those working on the frontline, and highlight the importance of the London Air Ambulance's vital work".
At the event, a young girl presented William with a handmade birthday card for the mother of three.
In fact, Royal author Katie Nicholl said, "William was quite concerned that the relationship had moved so quickly and being close to Harry, probably the only person close enough to say to Harry 'this seems to be moving quickly, are you sure?' And I think what was meant as well intended brotherly advice just riled Harry".
William also added, "I did remember this morning, so that was okay", to giggles from those gathered.