A Syrian boy receives treatment at a hospital in the regime-held part of Aleppo on October 13, 2016. Syrian state television said four children were killed by rebel rocket fire on a school in a western regime-held neighbourhood. (Photo by George Ourfalian/AFP Photo)

Saint Nicholas poses with students during a traditional parade in central Brussels, Belgium December 3, 2016. (Photo by Yves Herman/Reuters)

Performers dressed as Ded Moroz, the equivalent of Santa Claus, and his granddaughter Snegurochka (Snow Maiden) take on shoe covers as they visit the Republican Scientific and Practical Centre of Pediatric Surgery in Minsk, Belarus, December 28, 2016. (Photo by Vasily Fedosenko/Reuters)

Sikh devotee take part in Nagar Keertan procession on the occasion of Guru Gobind Singh birth anniversary in Allahabad, India on December 29, 2016. Guru Gobind Singh, born Gobind Rai (1666 – 1708), was the 10th Sikh Guru, a spiritual master, warrior, poet and philosopher. When his father, Guru Tegh Bahadur, was beheaded for refusing to convert to Islam, Guru Gobind Singh was formally installed as the leader of the Sikhs at age nine, becoming the last of the living Sikh Gurus. (Photo by Prabhat Kumar Verma/Pacific Press via ZUMA Wire/Rex Features/Shutterstock)

(L-R) Models Kylie Jenner and Kendall Jenner pose during the Universal, NBC, Focus Features, E! Entertainment Golden Globes After Party Sponsored by Chrysler held at the Beverly Hilton Hotel on January 8, 2017. (Photo by Christopher Polk/NBC/NBCU Photo Bank via Getty Images)

In this timed-exposure night photo taken early on February 12, 2017, Mount Sinabung volcano spews reddish smoke and ash, as seen from the Karo district in North Sumatra province. Activity levels have increased in the past week, with Sinabung shooting hot ash clouds into the sky dozens of times, according to the local volcano monitoring agency. (Photo by AFP Photo/Stringer)

Participants wearing costumes and masks take part in the first day of the traditional carnival parade in Mohacs, Hungary, 23 February 2017. The carnival parade of so-called busos, dressed in costumes with frightening wooden masks and using various noisy wooden rattlers, is traditionally held on the seventh weekend before Easter to drive away winter. (Photo by Sandor Ujvari/EPA)

A staff member sets up a ROBOTLEO robot at the Global Mobile Internet Conference (GMIC) 2017 in Beijing, China April 28, 2017. (Photo by Jason Lee/Reuters)