Newborns are usually able to open their eyes normally within a week of birth, but due to individual differences, some children are slower to develop but should be able to open their eyes normally by the end of the first month of life. Newborns may not be able to open their eyes normally at birth because their body functions are not fully developed, including the levator muscle, which lifts the upper eyelid. As the levator muscle develops, it will be able to lift the eyelid and open the eyes, a process that usually takes about a week. Because of individual differences, some newborns are a little slower to develop, so it is acceptable to take a longer time to open the eyes, but at the latest, they should be able to open their eyes normally by the time they reach one month of age. It is recommended that children with abnormal eye opening should be seen promptly for evaluation and treatment as prescribed by the doctor.