Kitten development is a process that occurs in the first six to 18 months of a cat's life. There are four main stages, each with its own unique characteristics. Though these broad stages can be broken down week by week, four main themes are identified: nursing, environment, weaning and status.
Week 1: Nursing
In the first week, a newborn kitten spends its entire time nursing and will double its weight in the first seven days. During this time, separation from the mother is detrimental to its development and health, as the constant nursing supplies the necessary vitamins and nutrients for certain faculties to completely form. Since the senses are not yet fully developed, separating the kitten from its mother may cause blindness or deafness. Likewise, the brain may not form properly, leading to mental inhibitions.
Weeks 2 Through 7: Environment
Around week two, the kitten will open its eyes, though its sight will not be fully functional until around the fifth week. The sense of smell and hearing are emerging and the kitten will become more aware of its environment, though interaction remains limited. The kitten's bones are not yet fully hardened, so walking is not yet experienced.
After the fourth week, all senses are generally developed and the kitten will start to explore its environment as it attempts to walk for the first time. Social interaction with the environment, people and other kittens will emerge near the fifth week and behavior is learned during this time.
Week 8: Weaning
Most mother cats will wean their kittens after eight weeks. Active play is now at its highest and will continue to be so as the kitten furthers its understanding of the environment and interacts with people and other cats. After the fourteenth week, playfulness will decrease slightly and the kitten will begin assuming a more mature composure.
6 to 18 Months: Status and Rank
At six months, the kitten's sense of status emerges, and a desire to dominate siblings or other pets may appear. In a litter this will take the form of aggressive play, snatching the siblings' food and "guarding" a certain area from the rest. Some kittens may even try to dominate other household pets or humans. This will continue until about 18 months, when the rank and status of each cat becomes generally established in the litter.
After 18 months, most cats are mature, though some species may not reach adulthood until two years.
As cats are not born with certain faculties fully developed, the time between birth and eighteen months is a crucial period that will determine his abilities and the functionality of his senses. Proper care is needed to ensure good development and lifelong health.