The youngest president in U.S. history is Theodore Roosevelt, who assumed office at the age of 42 after the assassination of William McKinley in 1901. However, if you're referring to the youngest elected president, that title goes to John F. Kennedy, who was inaugurated at 43 years old in 1961.
sir henery cotton
Nick Jonas
jean Kennedy
Beast Boy
roc royal
Aaron Cruden I think
Nick Jonas is the youngest singer
Roc Royal is the yongest
Harry Styles.
Harry Styles :)
Jonathan payton
Kennedy was the youngest person to be elected president. He was also the youngest president to die when he was killed.