A vendor sleeps as his son waits for customers at their roadside vegetable shop in New Delhi, February 12, 2019. (Photo by Adnan Abidi/Reuters)

A lioness drinks after being fed by senior keeper Glynn Hennessy at ZSL London Zoo on August 10, 2016 in London, England. Today marks World Lion Day which highlights the first global campaign to celebrate the importance and plight of lions worldwide. (Photo by Carl Court/Getty Images)

South American sea lion. Valencia, February 8, 2012. (Photo by Ger Art; Source: Flickr)

American soldiers leaping from an armoured personnel carrier during exercises in Korea, 17th March 1954. (Photo by Three Lions)

Tracy Raver's photos of babies – particularly sleeping babies – are adorable. The Nebraska-based photographer appeared on the Today Show Friday, September 11. Raver shoots portraits of babies at rest and in all sorts of positions. Full-bellies and a warm studio go a long way in coaxing the babies to sleep.

Londoners sleep on the platform and on the train tracks at Aldwych Underground station,London, during heavy all night Nazi bombing raids, October 8, 1940. (Photo by AP Photo)

A farmer sleeps near cows at the International Agricultural Show in Paris, France, February 29, 2016. The Paris Farm Show runs from February 27 to March 6, 2016. (Photo by Benoit Tessier/Reuters)

Indian men sleep in the shadow of an overflowing cloth container of hay, to be used as animal fodder, on a truck on a hot summer day in Ajmer in the western state of Rajasthan on May 30, 2018. (Photo by Shaukat Ahmed/AFP Photo)