Will my son's lazy eye go away on its own?

No: Lazy has come to mean a few things. If you mean the eyelid is droopy, this will not change on its own and should be evaluated by an oculoplastic surgeon/ophthalmologist to rule out horner's syndrome or other causes and then possibly corrected with surgery. If the eye itself is turning in or out, this should be evaluated by a pediatric eye doctor asap. Both problems can cause loss of vision.

No: See an eye specialist. Lazy eye may not go away. As time passes, the opportunity to remedy your son's problem may slip by. There is a window of time in which treatment of a lazy eye should occur. After that, it may be too late.