Two children jumping through a water hydrant's shower on a New York street. They have come from a neighbouring co-educational playgroup organised by the city's Police Department. (Photo by Orlando/Getty Images). 1950

Yoga Studio for ultra-Orthodox located at Ramat Beit Shemesh Nachal zohar 4/8, Israel. Separate classes for men, women and children. Occupations look quite funny... (Photo by Michal Fattal)

Children, wearing traditional Bavarian folk costumes specific to their region, prepare for the competition in the “Schuhplattler” style of Bavarian folk dancing for the Bavarian Lion Award at the Huosigau Heimat and Folklore Society on May 28, 2011 in Weilheim, Germany. (Photo by Johannes Simon/Getty Images)

Princess Elizabeth with her husband Prince Philip Duke of Edinburgh and their children Prince Charles and Princess Anne. (Photo by Keystone/Getty Images). August 1951

Participants dressed as Santa Claus gather shortly before the 4th annual Michendorf Santa Run (Michendorfer Nikolauslauf) on December 9, 2012 in Michendorf, Germany. Over 800 people took part in this year's races that included children's and adults' races. (Photo by Sean Gallup)

In this March 18, 2015 photo, a boy rides a mechanical bull for children at the Texcoco Fair on the outskirts of Mexico City. In Mexico, these types of fairs date back to Spanish colonial times, and in some smaller communities they are organized around the feast days of Roman Catholic saints. (Photo by Eduardo Verdugo/AP Photo)

Patients from Rady Children's Hospital hug a bottlenose dolphin after being invited to swim and interact with dolphins at Sea World in San Diego, California August 27, 2015. Sea World has hosted Dolphin Interaction Program for seven years. It was started by dolphin trainer Joy Soto who battled and overcame non-Hodgkin’s lymphoma. (Photo by Mike Blake/Reuters)

Children guarded by Hungarian police play on the ground after being detained along with other migrants who illegally crossed from Serbia to Hungary near the village of Asotthalom, Hungary, September 16, 2015. (Photo by Dado Ruvic/Reuters)