Four-month-old fox cubs squaring up to each other in Walthamstow, England on August 7, 2015. (Photo by Greg Morgan/Barcroft Media)

The nearly four-week-old Tapir cub bathes on June 28, 2016 in Gondwanaland at the zoo in Leipzig, Saxony. (Photo by Jan Woitas/DPA)

Revelers dance at the Old Settler's Music Festival in Driftwood, Texas, U.S. on April 22, 2017. (Photo by Mohammad Khursheed/Reuters)

Replica of an old traditional Icelandic house from the 1800 with eruption of Iceland's Eyjafjallajökull volcano, 2013. (Photo by Ingólfur Bjargmundsson/Getty Images)

These stunning photographs show the changing face of a majestic centuries old Kazakh pastime tradition that still lives in the lands of mongolia – eagle hunters. Photo: 13 year old Irka Bolen with his eagle. Tradition wise, when a boy turns 13, then are strong enough to hold the weight of a fully grown eagle. (Photo by Asher Svidensky/Caters News)

The figure of an eight-year-old boy is seen inside a suitcase on a Spanish civil guard scanner screen at the border between Morocco and Spain's north african enclave Ceuta, Spain in this handout photo released May 8, 2015. A 19-year-old woman was arrested May 7, 2015 for the attempted smuggling of the boy, who was checked by medics and handed over to juvenile prosecutors office, according to authorities. (Photo by Reuters/Ministerio Del Interior)

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)

Three-years-old dog Hope uses a wheelchair to run next to its owner Regine Grosinger in Vienna September 3, 2014. Hope was found with cut-off back legs in the countryside and brought to an animal asylum when it was four-month-old. Grosinger took the dog home two months later and had a wheelchair manufactured for it. (Photo by Heinz-Peter Bader/Reuters)