A young arab boy, armed with a rifle and a knife, in the Aden Protectorate near Yemen. (Photo by Richards/Fox Photos/Getty Images). February 1938

The Lady Boys of Bangkok have fun at the Meadows August 1, 2006 in Edinburgh, Scotland. (Photo by Jeff J Mitchell/Getty Images)

A British policewoman chasing after a group of naked street boys by the Serpentine in Hyde Park, London. (Photo by Reg Speller/Getty Images). 1926

A boy does a bicycle kick as he practises on the Marina beach ahead of the World Cup soccer tournament in Brazil, in Chennai June 4, 2014. REUTERS/Babu

Tony Appleton, a town crier, announces the royal birth outside the Lindo Wing of St Mary's Hospital after Catherine, Duchess of Cambridge gave birth to a baby boy in central London July 22, 2013. Prince William's wife Kate gave birth on Monday to a baby boy, in the Lindo Wing of St Mary's Hospital, who becomes third in line to the British throne, his office said. The royal baby, the couple's first child, was born at 4:24 p.m. (15:24 GMT), weighing 8 lbs and 6 oz. (Photo by Lefteris Pitarakis/Associated Press)

Afghan boys attend their Quran study sessions at the Islami Noor religious school on May 12, 2011 in Kandahar, Afghanistan. Despite recent multiple attacks near the city's downtown, children continue their studies at the school. (Photo by Majid Saeedi/Getty Images)

Boys play basketball in the facilities of Belarus' Republican Clinic of Speleotherapy within a salt mine, as part of their treatment, near the town of Soligorsk, south of Minsk, February 19, 2015. According to the state clinic, more than 7,000 children and adults seek medical treatment for respiratory illness each year in the subsurface chambers of its facilities, located 420 metres underground between layers of potassium and stone salts in an operational salt mine. (Photo by Vasily Fedosenko/Reuters)