A young boy plays with soap bubbles near Hofburg Palace at Heldenplatz, one of the top tourists attractions in Vienna, Austria, January 26, 2016. (Photo by Christian Bruna/EPA)

A participant plays a game on her phone as others watch during a break in a traditional Chinese opera competition at the National Academy of Chinese Theatre Arts in Beijing, China, November 26, 2016. (Photo by Thomas Peter/Reuters)

Children play with weapons during Children's Day celebration at a military facility in Bangkok, Thailand January 14, 2017. (Photo by Jorge Silva/Reuters)

Children play on a donkey cart belonging to an elderly Afghan refugee sleeping on a roadside on the outskirts of Islamabad, Pakistan, Wednesday, February 18, 2015. (Photo by Muhammed Muheisen/AP Photo)

In this Friday, January 24, 2014 photo, Afghan refugee girl, Robina Haseeb, 5, poses for a picture, while playing with other children in a slum on the outskirts of Islamabad, Pakistan. (Photo by Muhammed Muheisen/AP Photo)

Flash, a golden retriever, plays with a toy following a press event for the American Kennel Club to reveal the nations most popular dog breeds in the Manhattan borough of New York, February 22, 2016. (Photo by Carlo Allegri/Reuters)

Indigenous Sahrawi girls play on an improvised see-saw at a refugee camp of Boudjdour in Tindouf, southern Algeria March 3, 2016. UN Secretary General Ban Ki-moon is scheduled to visit the Sahrawi refugees in south-west Algeria's Tindouf region. (Photo by Zohra Bensemra/Reuters)

Children play at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, March 29, 2016. (Photo by Marko Djurica/Reuters)