British underwater photographer of the year 2021, British waters wide angle category winner and My Backyard category winner. While You Sleep by Mark Kirkland (United Kingdom), common frog taken in Malls Mire, Glasgow, Scotland. (Photo by Mark Kirkland/Underwater Photographer of the Year 2021)

A reveller sleeps on the pavement during the Sanja Matsuri festival in the Asakusa district of Tokyo May 17, 2015. The Sanja Matsuri festival attracts over about one million visitors over its duration of three days, when parties of revellers carry portable shrines through the Asakusa neighbourhood, rocking and shaking them in a belief that this intensified the powers of the deities that reside inside them. (Photo by Thomas Peter/Reuters)

A homeless man sleeps against a wall adorned with a mural featuring a Shipibo Indigenous girl and Amazon rainforest animals, in Pucallpa, in Peru's Ucayali region, Wednesday, September 2, 2020. Peru is home to one of Latin America's largest Indigenous populations, whose ancestors lived in the Andean country before the arrival of Spanish colonists. (Photo by Rodrigo Abd/AP Photo)

Muslim girls are seen after prayers, in Lagos, Nigeria, Friday, July 31, 2020. Small groups of pilgrims performed one of the final rites of the Islamic hajj on Friday as Muslims worldwide marked the start of the Eid al-Adha holiday amid a global pandemic that has impacted nearly every aspect of this year's pilgrimage and celebrations. The last days of hajj coincide with the four-day Eid al-Adha, or “Feast of Sacrifice”, in which Muslims slaughter livestock and distribute the meat to the poor. (Photo by Sunday Alamba/AP Photo)

A novice Bhutanese monk sleeps after hours of prayer waiting for class to be over at the Dechen Phodrang monastery October 18, 2011 in Thimphu, Bhutan. The monks average about 10 hours of study a day waking up at 5:00am. (Photo by Paula Bronstein/Getty Images)

Dancers Amy Hadley and Bethany Kingsley-Garner from the Scottish Ballet wait backstage during the dress rehearsal of the current production of “Sleeping Beauty” at the Theatre Royal on December 16, 2011 in Glasgow, Scotland. (Photo by Jeff J Mitchell/Getty Images)

This adorable and unlikely pair of best friends are inseperable. Kitty the kitten was abandoned and Buttons the Jack Russell was rejected by his mum. They eat, sleep and play together while they are being hand reared at our centre in Old Windsor, Berkshire. We would love for them to find a new home together when they are ready to leave our care in the near future.

Four-year-old Rashida from Kobani, Syria, part of a new group of more than a thousand immigrants, sleeps as they wait at border line of Macedonia and Greece to enter into Macedonia near Gevgelija railway station August 20, 2015. (Photo by Ognen Teofilovski/Reuters)