Children watch a rabbit, jumping over a hurdle at an obstacle course the 5th Open Rabbit Sport Tournament (5. offene Kaninchensport Turnier) on August 28, 2011 in Rommerz near Fulda, Germany. Eighty rabbits competed in light-weight, middle-weight and jumping-for-points categories at today's tournament in Rommerz that is based on Kanin Hop, or Rabbit Hopping. Rabbit Hopping is a growing trend among pet rabbit owners in Central Europe and the first European Championships are scheduled to be held later this year in Switzerland. (Photo by Ralph Orlowski/Getty Images)

An Afghan child practices walking with his new prosthesis at the International Committee of the Red Cross (ICRC), orthopedic center on September 10, 2011 in Kabul, Afghanistan. After more than 30 years of war and a decade since the 9/11 attacks in the United States, thousands of Afghans, both military and civilian, continue to pay a heavy price from the conflict. The ICRC center makes prosthetics for amputees and helps them, as well as Afghans with spinal injuries and children with congenital birth defects, to learn to walk. (Photo by John Moore/Getty Images)

Four-year-old Chinese boy Huang Yang plays with five-year-old beluga whale Xiao Xin at the Qingdao Ocean World on November 3, 2007 in Qingdao of Shandong Province, China. Huang Yang began swimming as a baby and fell in love with the whale after watching its performance. On the International Children's Day, June 1 this year, the Qingdao Ocean World has made the boy's dream come true when they allowed Huang Yang to swim with the beluga whale. (Photo by China Photos/Getty Images)

Santa Claus rides in his sleigh as he prepares for Christmas in the Arctic Circle near Rovaniemi, Finland December 15, 2016. At Santa Claus' Lapland home in Finland, his helpers sort out piles of letters from around the world, each detailing children's requests for this Christmas. (Photo by Pawel Kopczynski/Reuters)

A child rescued from Boko Haram in Sambisa forest is seen at the Internally Displaced People's camp in Yola, Nigeria May 3, 2015. Hundreds of traumatised Nigerian women and children rescued from Boko Haram Islamists have been released into the care of authorities at a refugee camp in the eastern town of Yola, an army spokesman said. (Photo by Afolabi Sotunde/Reuters)

Revelers dance and shout as they listen to music, in front of the main stage, during the 21st Woodstock Festival in Kostrzyn-upon-Odra, Poland July 31, 2015. An estimated 200,000 people attended the ongoing festival, a brainchild of Polish journalist and social campaigner Jerzy Owsiak, on Friday. Owsiak initiated the event to say thank you to those who donated money to his GOCC charity organisation that delivers medical care for children. (Photo by Kacper Pempel/Reuters)

A worshipper wearing a kerchief with the image of the Our Lady of Fatima attends a mass at the Our Lady of Fatima shrine, in Fatima, central Portugal, Wednesday, May 13, 2015. Every year on May 12 and 13 tens of thousands of Catholic believers go on pilgrimage to the Fatima sanctuary to pray and attend masses where the apparitions of the Virgin Mary were witnessed by three shepherd children Lucia, Jacinta and Francisco in 1917. (Photo by Francisco Seco/AP Photo)