There has been a change in the Swedish royal calendar indicating that Queen Silvia will attend the funeral. She and the King were both scheduled to visit the Olympic games in Korea, but the calendar now only states that King Carl Gustaf will visit. She might also be accompanied by one or two of his sisters, who are cousins of Queen Margrethe.
King Harald and Queen Sonja have no engagements on February 20, and are both likely to attend even if it is a private event (they are very close to Queen Margrethe). Possibly also their children.
Among the British royals, almost all have other engagements on that day, leaving the Duke of York or the Wessexes as the most likely representatives (if any).
The Belgian royal family has their annual commemoration service for deceased members of the family on February 20, which makes it unlikely with senior representatives from that country.
The Dutch royal family has nothing scheduled as far as I can see, they are on vacation in Lech this week it seems. No official events in the Luxembourg calendar either.
The Spanish King has an engagement (he was not likely to attend anyway), and the family is most likely to be represented by Queen Sofia.
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