Babies can’t tell you if their vision is blurry or if they can’t focus their eyes. But there are subtle ways you can tell.

If your baby never seems to focus on objects or they have a hard time finding close objects like your face or hand, let your pediatrician know. Watch for signs in school-age children like squinting, difficulty reading, or sitting too close to the TV.

If your child isn’t performing well in class, make sure to ask if they can see the blackboard. Many children are labeled “poor students” or “disruptive,” or are even diagnosed with ADHD, when they actually have unidentified poor vision. Constant eye rubbing is another sign of potential vision problems.