Babies are young, many parents like to sleep with the lights on at night for fear of their children being afraid of the dark, or for the convenience of caring for them. But did you know that this kind of care from you may leave your baby with hidden vision problems. What is this all about? A study in the United States found that around the age of 2 years is an important period of eye development, and the association between the sleeping light source and vision at this time is very close. The survey showed that if the child sleeps in a dark room before the age of 2, the proportion of myopia is 10%; if the child sleeps in a room with a small night light before the age of 2, the proportion of myopia is 34%; if the child sleeps in a room with a large light on before the age of 2, the proportion of myopia is 55%. So parents should pay enough attention to the light environment in which children live, especially the indoor light environment, to avoid unnecessary excessive light. For children who are afraid of the dark, they should avoid the habit of falling asleep under the light when they are young, and parents can sleep with their children and turn off the light after they fall asleep, while avoiding direct light on their eyes. In addition, parents should pay attention to children’s reading and writing habits, reduce the time spent watching TV and operating computers, and have regular checkups by pediatric ophthalmologists in order to effectively avoid myopia.