A six-day-old hippopotamus is pictured next to his mother, Kara, aged 21, on September 12, 2012 at “Planet sauvage” (“Wild planet”) Zoo in Port-Saint-Pere, western France. The birth, a rare event for this species in captivity, occured on September 7, 2012 in the Zoo. (Photo by Frank Perry/AFP Photo)

Karis, a one month old lion cub being weighed at Blair Drummond Safari Park near Stirling, Scotland, Thursday October 10, 2013. Weighing in at 5kg, the cub will stay with her mother, Teekay until she is 12 weeks old before they are returned to the pride. (Photo by Andrew Milligan/AP Photo/PA Wire)

In this Monday, June 20, 2016 photo, a Palestinian girl plays in a barrel as her mother bakes bread for a Ramadan dinner at their house in el-Zohor slum, on the outskirts of Khan Younis refugee camp, southern Gaza Strip. (Photo by Khalil Hamra/AP Photo)

Baby giraffe of Niger (Giraffa Camelopardalis) “Kenai” (R), born on August 25, 2016, kisses his mother “Dioni” on August 31, 2016 at the zoo of La Fleche, northwestern France. (Photo by Jean-Francois Monier/AFP Photo)

The Enemy, 1944. With the outbreak of world war two, photojournalism was enlisted in defence of Mother Russia. In this photo by Anatoli Egorov, who was wounded in action, corporal Stepan Vasiljevich Ovcharenko shoots at enemy troops with a machine gun. (Photo by Anatoli Egorov/Lumiere Brothers Center for Photography)

Ma Jiaqi, 5, and her mother arrive at Beijing Railway Station for their train to Changchun of Jilin province, in Beijing, China, January 25, 2016. According to traffic police, over 2.9 billion trips will be made around China during the 40-day Spring Festival travel rush, which started on January 24. (Photo by Jason Lee/Reuters)

The mother (2nd R) of missing firefighter Xue Ning is helped by other family members as she cries outside the venue of a news conference after trying to demand for more information from government officials, following the explosions on Wednesday night at Binhai new district in Tianjin, China, August 15, 2015. (Photo by Jason Lee/Reuters)

Aimee, 19, who has Down syndrome, has make-up applied by her mother before a presentation in Monterrey, Mexico, in this picture taken April 9, 2016. The association “Abrazame con Discapacidad” (“Embrace me with Disabilities”) teaches folk dance to low-income people with Down syndrome and manages presentations at public events where they receive a payment, as part of a therapy that helps improve their motor system, learning and self-esteem, the association said. (Photo by Daniel Becerril/Reuters)