Congratulations on your new kitten! As you watch your little new furbaby grow, you may want to know when the little one will start grooming, using the litter box, or be considered an adult. Find out below about the life changes and stages your new kitten will grow through. Four kitten milestones 2 weeks: The kittens eyes start to open and its sense of smell begins developing. Fun fact: All kittens are born with blue eyes! 3 weeks: The kittens sense of smell is fully developed, its ears become erect, and baby teeth begin to appear. 4 weeks: The kitten starts to explore and will start grooming. 5 weeks: The…