The Duchess of Cambridge played tennis with the US Open Champion. Denmark had an event every day of the last four. King Willem-Alexander and Queen Máxima celebrated classical music and the announcements for Princess Amalia's 18th birthday have started. Crown Prince Haakon learned about Norway's entrepreneurial scene. King Felipe and Queen Letizia were in Portugal to open a world first. King Carl Gustaf and Crown Princess Victoria both had military engagements on Friday.