A couple hugs while standing near a Christmas tree made out of plastic bins and plastic hampers outside the Museum of History in Monterrey, Mexico, December 4, 2015. The humble Christmas tree has a rich history, from evergreen trees used to symbolise eternal life in Ancient Egypt to tree worship among pagan Europeans. The modern version has its origins in Germany, where the song “O Tannenbaum” is still a festive favourite. Today the traditional tree with lights and decorations appears in cities including Washington, Moscow and Beirut. Alternative constructions range from recycled rubbish in Mexico City to old window frames in Rakvere, Estonia. Whatever the shape or size, the message is the same: Merry Christmas. (Photo by Neil Hall/Reuters)

Pokot men carry a part of a carcass of a bull killed by a young man during an initiation ceremony in Baringo County, Kenya, January 20, 2016. Far from the bustling city of Nairobi, in an isolated corner of Kenya's Rift Valley, young men from the Pokot community spear a bull in a ceremony called Sapana that takes them into adulthood. (Photo by Siegfried Modola/Reuters)

A young boy lifts heavy bricks as he works at brick factory around Kathmandu valley. (Photo by Narendra Shrestha/EPA)

A young Free Syrian Army fighter holds a rifle in Haresta neighbourhood of Damascus January 16, 2013. (Photo by Goran Tomasevic/Reuters)

Young girls attend a training session in MGFSO Olympic reserve school in Moscow on May 30, 2016. (Photo by Kirill Kudryavtsev/AFP Photo)

Young gymnasts practice pull-up on a bar at a gymnasium of a sports school in Jiaxing, Zhejiang province April 11, 2015. (Photo by William Hong/Reuters)

Attendees at Wizard World Comic Con walk through hallways in Chicago, Illinois, United States, August 22, 2015. (Photo by Jim Young/Reuters)

A young festivalgoer jumps to burst a bubble at Latitude Festival at Henham Park, Britain, July 22, 2021. (Photo by Peter Cziborra/Reuters)