Prince Harry just celebrated his 37th birthday on September 15, and the estranged royal seems a world away from the cheeky three-year-old who stuck his tongue out at photographers on the balcony of Buckingham Palace. The trauma of losing his mother at just 12 coupled with the pressures of public life have weighed very heavily on the father-of-two, who’s been outspoken about his mental health struggles, particularly over the past year.