Prince Albert of Monaco was on hand for his son Alexandre Grimaldi’s 20th birthday celebration! The royal, 65, was pictured sitting next to his eldest son in a photo shared by Alexandre’s mother, Nicole Coste, on Friday, Aug, 25.

Albert’s 31-year-old daughter, Jazmin Grace Grimaldi, was seated at the outdoors table across from her father. Nicole also shared a picture of her son’s birthday cake. Alongside the photos, she wrote: “Happy birthday Alexandre ♥️.”

Jazmin, whose mother is Tamara Rotolo, took to her Instagram Story to post a photo of her half-brother’s birthday cake. In addition to Alexandre and Jazmin, Prince Albert is a father to eight-year-old twins Prince Jacques and Princess Gabriella, whom he shares with his wife Princess Charlene.

Albert, who married Charlene in 2011, acknowledged in 2005 that he had fathered a son with Nicole. Ahead of Alexandre’s milestone birthday this year, the Prince’s son spoke with Point de Vue about his surname Grimaldi. “My father’s name is Grimaldi. It makes sense that I bear his name. I would have been called Dochomel if my father had been Mr. Dochomel!” Alexandre told Point de Vue (via HELLO!). “Besides, I never called myself Coste or Coste-Grimaldi. On no ID, at school or on my diplomas. Those who call me that have a malicious attitude.”

“Nor am I ‘illegitimate’ since when I was born, neither of my parents was in another marriage, and they did not commit adultery. Using that word is insulting!” Alexandre continued. “I hope no one believes the lies conveyed on the internet. 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. Not from a judge or the press who have forced him to.”