BEIJING, CHINA - SEPTEMBER 24: Crown Prince Frederik of Denmark poses for a picture on the terrace of the Gehua Plaza after the signing ceremony between Danish and Chinese companies that will work together on the Qinlong Hutong renovation project, on September 24, 2017 in Beijing, China. (Photo by Etienne Oliveau/Getty Images) (Getty Images)
Denmark's Crown Prince Frederik left the Winter Olympics in Pyeongchang, South Korea, Friday to rush home because the condition of his father — the French-born husband of Queen Margrethe — has "seriously worsened."
Prince Henrik was hospitalized Jan. 28 for a lung infection with doctors saying they had found a benign tumor in his left lung.
Crown Prince Frederik, an International Olympic Committee member, left Pyeongchang before the official opening of the Winter Games, according to Denmark's National Olympic Committee.
Frederik's wife, Australian-born Crown Princess Mary, and two of the couple's four children briefly visited Copenhagen's university hospital, where her father-in-law is a patient, Danish media reported.
Henrik's brother, Etienne de Montpezat, declined to speak to The Associated Press Friday, but was quoted by Danish newspaper BT as saying "it seems to be a matter of weeks."
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A friend of the prince's, Erik Brandt, told tabloid Ekstra Bladet that Frederik rushing home meant "that here is something wrong."
Last year, the palace announced that the 83-year-old prince was suffering from dementia.
Hundreds of Danes wrote on the royal household's Facebook page Friday, expressing hopes for the prince's quick recovery and offering warm thoughts to Henrik and the family as a whole.
Under Denmark's Constitution, the royal family has no political power and is barred from involvement in party politics.
Henrik often voiced his dissatisfaction with not being the queen's equal after she acceded to the throne in 1972, causing a stir in one of the world's oldest monarchies. For years, Henrik has complained that he didn't become king instead.
A change to the Danish Constitution in 1953 allowed female succession, paving the way for Margrethe to become the monarch. Even before that, Henrik wouldn't have become king.