Mark Taylor / Cheeky ginger kitten, Ollie, 10 weeks, reaching up and batting the ear of Boxer puppy

Philippe Clement / Two Lynx (Lynx lynx) kittens play fighting in front of den entrance, Bavarian Forest National Park, Germany, October. Captive.

Valeriy Maleev / Pallas's cat kitten (Otocolobus manul) Sukhe-Batar Aimag, South Gobi Desert, Mongolia. June.

Philippe Clement / European wildcat (Felis silvestris silvestris) sitting on a rock, with kittens playing nearby, Bavarian Forest National Park, Germany, May. Captive.

Jane Burton / British Shorthair kittens, Benedict, ginger, and Joan, silver tabby.

Mark Taylor / Black-and-white kitten, Loona, age 11 weeks, arching back.

Mark Taylor / Black and white Border collie looking sideways at black and white kitten.

Mark Taylor / Tabby kitten, Picasso, age 3 months, sleeping on a fluffy rug.

Mark Taylor / Tabby kitten, 6 weeks, standing on hind legs.

Mark Taylor / Tabby kitten, 6 weeks, lying with head up and raised paw.

Mark Taylor / Tabby kitten, 6 weeks, standing.

Mark Taylor / Tabby-and-white Siberian-cross mother cat carrying her tabby kitten, 4 weeks.