An adult chimp plays with a young chimp at Chimp Haven in Keithville, La., Monday, February 18, 2013. One hundred and eleven chimpanzees will be coming from a south Louisiana laboratory to Chimp Haven, the national sanctuary for chimpanzees retired from federal research. (AP Photo/Gerald Herbert)

An actor carries a cross as he plays the role of Jesus Christ in a re-enactment of the Via Crucis (Way of the Cross) during a Holy Week procession, in preparation for Good Friday celebrations, in Luque, Paraguay, on March 27, 2013. Holy Week is celebrated in many Christian traditions during the week before Easter. (Photo by Jorge Adorno/Reuters)

In this Friday, December 5, 2014 photo, Iranian volunteer Asal Moghaddam plays with dogs at the Vafa Animal Shelter in the city of Hashtgerd 43 miles (73 kilometers) west of the capital Tehran, Iran. More than 500 dogs find care and affection at the Vafa Animal Shelter, which was established through an endowment in 2004 and is the country’s only licensed animal refuge. (Photo by Vahid Salemi/AP Photo)

Children play on an abandoned car near a protest, which is against the dissolution of Yemen's parliament and the Shi'ite Muslim Houthi militia's tightening grip on power, in the southwestern city of Taiz, February 13, 2015. (Photo by Mohamed al-Sayaghi/Reuters)

Swedish brown bears “Fred” and “Frode” play in the snow on January 30, 2014 at the Natur- und Umweltpark (NUP) animal park in Guestrow, northeastern Germany. Despite of icy temperatures, the bear brothers took a break from their winter rest. (Photo by Bernd Wuestneck/AFP Photo/DPA)

A man playing the part of a zombi pretends to rise from the dead from inside a coffin at a Carnival parade in Jacmel, Haiti, Sunday, February 23, 2014. The pre-Lent festival began in the streets of this town known for its arts to kick off Haiti’s Carnival festivities. (Photo by Dieu Nalio Chery/AP Photo)

A white Bengal tiger cub plays with its mother in a zoo in the Siberian city of Novosibirsk, about 2,800 kilometers (1,750 miles) east of Moscow, Russia, Tuesday, April 21, 2015. Two blue-eyed Bengal tiger cubs were born in March to a couple of white tigers at Novosibirsk zoo. (Photo by Ilnar Salakhiev/AP Photo)

A security personnel plays with a girl in the compound of a health and rest centre which serves as a temporary accommodation for refugees from eastern regions of the country in the town of Korostyshiv, Zhytomyr region, Ukraine, July 30, 2015. More than 400 people who left eastern Ukraine due to a military conflict have arrived at the sanatorium in Korostyshiv since the summer of 2014, according to representatives. (Photo by Valentyn Ogirenko/Reuters)