On Sunday, Alexandre Grimaldi, the second-born child of Monaco’s Prince Albert, turned 20, and he is celebrating with a series of events in the small coastal principality. His mother, Nicole Coste, posted photos to her Instagram that show her, Alexandre, and Albert with Alexandre’s half-sister Jazmin Grace Grimaldi and a few friends. On her Instagram story, Coste later posted footage from a nightclub party also celebrating Alexandre. 

Alexandre, a university student, is not in line for the throne of Monaco because Coste and Albert were not married when he was born in 2003. In a recent interview with the French magazine Point de Vue, he explained that he finds news reports that call him “illegitimate” to be offensive and inaccurate. “Using that word is insulting! I hope no one believes the lies conveyed on the internet,” he said. “One bears the name of one’s father when one has been recognized since birth. I had voluntary recognition from my father when I was a baby.”

Absent from the birthday celebrations were Alexandre’s stepmother, Princess Charlene, and his 8-year-old half-siblings Prince Jacques and Princess Gabriella. Last week, Charlene made headlines for deleting her personal Instagram account, where she had long shared pictures of her royal duties and day-to-day life. Though the Instagram account for the Fondation Princesse Charlène de Monaco, her charity, is still active, the deactivation has revived speculation that her marriage to Prince Albert is in trouble. 

Albert and Charlene have been married since 2011 and faced rumors that their relationship is in turmoil for nearly as long. Earlier this year, the couple’s spokesperson took the rare step of denying a round of rumors with a forceful statement. “I would like to formally deny the malicious rumors peddled by the French magazine Royauté,” it read. “Please disregard this article which is totally unfounded.” 

But earlier this month, speculation began again when the French tabloid Voici spoke to an anonymous source who said the pair is merely a “ceremonial couple” and that Charlene is actually residing in Switzerland full time. In response, an anonymous source told the German newspaper Bild that they are “good partners” and “take turns taking care of the children.”

Charlene and Albert appeared together at the coronation of King Charles III in May, and were also seen together at the Formula 1 Grand Prix later that month. Their last joint appearance was a night at the Red Cross Ball in Monte Carlo on July 29.