When kittens are born they rely completely on their mother. As a necessary first function, the mother cat will lick her kittens right after birth to help start their breathing. She also does this after they eat to help stimulate digestion. Kittens are born with their eyes and ears closed. For the first three weeks a kitten's life entails eating and sleeping. During this time they huddle with their mother and littermates to keep warm. Kittens begin to open their eyes when they are around 8 days old and generally they are fully open by the 14th day. An intriguing fact is that all cats are born with blue eyes. The 'adult' eye color begins to appear after 3 to 12 weeks. Kitten's ears open between the 5th and 8th day, and are generally up strait by three weeks. Crawling starts at 18 days and standing at 21 days. The kitten will start to orient itself by sight and sound around the 25th day.

One sign of a healthy kitten is that it is firmly packed and nurses vigorously. A kitten should double its weight in the first week. Unless there is a health problem, kittens should be handled very little during the first three weeks. Being close to its mother and littermates is very important for the proper development of a kitten. Two of the most important health factors for a kitten are that it eats well and stays warm. Kittens can lose body heat rapidly if not kept warm. This can be life threatening. When kittens sleep they will often move and twitch. This is called activated sleep it helps the kitten develop muscle tone.

By the fourth week, most of the kitten's senses are well developed. At this stage the kitten interacts with its littermates, its teeth will begin to come in, and it will begin walking. By the fifth week, the kitten's sight is developed. Its motor skills and social interactions will be well developed and the kitten will be able to groom itself. At this time, there will be a change towards an adult sleep pattern.

Between 7 and 14 weeks a kitten learns mainly by playing. For this and other reasons, it is recommended that a kitten be at least 10 to 12 weeks old before adoption. At 3 to 6 months the kitten will start to develop and understand social structures and territory. From 6 to 18 months a kitten learns by exploring and challenging boundaries. A kitten will physically mature to an adult cat at this point.