All kittens are born with blue eyes. This blue color is due to a lack of pigment called melanin in the iris, which hasn't developed yet at birth. As kittens grow, usually around 6 weeks of age, melanin production begins, and their eye color may change to their permanent adult color, which can be yellow, green, orange, or brown. However, some cats, particularly certain breeds like Siamese and Ragdoll, retain blue eyes into adulthood due to genetic factors limiting melanin development.
So, while all kittens start with blue eyes, not all adult cats keep blue eyes. The change or retention depends on genetics and pigment production.
