Yva Momatiuk & John Eastcott / Grizzly Bear (Ursus arctos horribilis) mother with two 4 month old cubs sitting in grass together, Katmai National Park, Alaska

Richard Du Toit / Cheetah (Acinonyx jubatus) adult female laying in the grass with her three month old cubs, summer, Phinda Game Reserve, South Africa

Yva Momatiuk & John Eastcott / African Lion (Panthera leo) three month old cub climbing tree stump, Masai Mara National Reserve, Kenya

Yva Momatiuk & John Eastcott / African Lion (Panthera leo) adult male followed by curious and playful six and three month old cubs, Masai Mara National Reserve, Kenya

Mitsuaki Iwago / African Lion (Panthera leo) three month old cub sleeping on mother's leg, Ngorongoro Conservation Area, Tanzania

Gerry Ellis / Koala (Phascolarctos cinereus) mother and joey, three month old, Australia

Gerry Ellis / Koala (Phascolarctos cinereus) mother and three month old joey in tree, Australia

Gerry Ellis / Koala (Phascolarctos cinereus) mother and joey, three month old, Australia

Tui De Roy / Campbell Albatross (Thalassarche impavida) portrait of two month old chick awaiting parent's feeding, Bull Rock, North Cape Colony, Campbell Island, New Zealand

Mitsuaki Iwago / Polar Bear (Ursus maritimus) mother with three month old cubs, Wapusk National Park, Manitoba, Canada

Mitsuaki Iwago / Polar Bear (Ursus maritimus) portrait of mother with three month old cubs, Wapusk National Park, Canada

Eric Baccega / Polar bear with two 3m-old cubs {Ursus maritimus} Churchill, Manitoba, Canada