One of the most interesting things a new parent can see is their baby’s eye crossing for the first time. It can be startling and worrisome, but it is completely normal. 

Fun fact: Newborn babies are actually born legally blind. They can only see about 8 to 12 inches, which is about the distance from an adult’s chest to his or her face. Everything beyond that distance is movement and shadows. 

Between birth and one month old, every baby’s eyes will wander, sometimes in different directions. This happens more frequently when the baby is changing focal length – adjusting their eyes from looking at something close to something farther away – and when the baby is tired. 

When a baby is around three months old, they should no longer be crossing their eyes, or letting their eyes wander separately. If a baby’s eyes are still crossing or wandering at this age, it is time to talk with a doctor about it. 

Babies crossing their eyes after the three month mark are usually experiencing one of the following: 

  • Pseudostrabismus: An optical illusion where it looks like the baby’s eyes are crossing when they actually are not. This is common and occurs when babies have a wider bridge of their nose or larger flaps of skin in the corners of their eyes. 
  • Strabismus: This rare condition is truly crossed eyes, and is caused by muscle weakness in one eye more than the other. 
  • Amblyopie: This condition is caused by strabismus. The baby will experience decreased vision in the crossed eye as the eye wanders. This condition can be treated and corrected with early intervention. Treatment typically includes wearing a patch or cover over the eye with better vision, as this will cause the muscles of the weaker eye to grow stronger. 

If you have any questions about your baby’s vision, talk to the pediatrician.