Meet The World's Royal Teenagers

Prince Christian of Denmark is the 15-year-old son of Crown Prince Frederik and Crown Princess Mary. He is their eldest son, but the second-in-line to the throne. He is second-in-line because his grandmother, Queen Margrethe II of Denmark, is the current reigning monarch, and his father, Prince Frederik will be the next one to succeed to the throne. 

Prince Christian has three younger siblings, and the four of them are proving to be modern royals. For example, Christian was the first Danish royal to attend a public school.