A member of Red Noses Clowndoctors entertains migrants before their departure to Austria at a registration center in Dobova, Slovenia, December 27, 2015. (Photo by Srdjan Zivulovic/Reuters)

Internally displaced Syrian children stand at the entrance of their makeshift shelter that is an underground cave in Om al-Seer, southern Idlib countryside, Syria December 26, 2015. (Photo by Khalil Ashawi/Reuters)

Girls play with their new dolls during the distribution of free toys for low-income families and a picture on the lap of one of the Three Wise Men at Almudena Cathedral in Madrid, Spain, December 22, 2015. Traditionally, children in Spain receive their presents delivered by the Three Wise Men on the morning of January 6 during the Christian holiday of the Epiphany. (Photo by Susana Vera/Reuters)

An internally displaced woman collects water from a pond to construct a mud-house at the Aboushok camp in El Fasher, North Darfur, Sudan, November 17, 2015. The conflict in Sudan's Darfur region that erupted 12 years ago shows no sign of ending. But it hasn't stopped displaced youngsters, some of whom have spent their entire lives in refugee camps, from dreaming big. Twelve children aged 12 explain their hopes and dreams for the future; ambitions include becoming a doctor, an engineer and a teacher. (Photo by Mohamed Nureldin Abdallah/Reuters)

When Ed Templeton was a young skateboarder in California, he took Polaroids of his friends smoking at their local park. Those pictures in 1994 were the start of a lifelong habit – Templeton has been capturing youngsters all over the world experimenting with cigarettes ever since. Here: Santiago, Chile, 2002. (Photo by Ed Templeton/Robert & Tilton Gallery, Culver City)

A girl carries on her head a pile of dried shrubs she gathered for cooking and heating, in Kabul, Afghanistan November 18, 2015. (Photo by Omar Sobhani/Reuters)

Ramela Meseljevic, a 7 year-old girl born without both of her hands and one of her legs shorter than the other, writes during classes in the her school in Begov Han, Bosnia and Herzegovina December 2, 2015. International Day of Disabled Persons is observed on December 3 with the theme "Inclusion matters: access and empowerment of people of all abilities". (Photo by Dado Ruvic/Reuters)

Unnati, 6 years old, at home with his sister Ishika, 4 years old, in the Mahamai Ka Bagh neighborhood. Unnati was born to parents contaminated by a carcinogenic and mutagenic water supply. This year marks the 31st anniversary of the 1984 Union Carbide gas tragedy that killed thousands of citizens of Bhopal within 72 hours and has gone on to claim thousands more as a result of the polluted environment. (Photo by Giles Clarke/Getty Images)