Fixation of the eyes on an object develops by about 3 months. However if she is having significant light sensitivity please check if there is any white lesion on the black portion of the eye which we call as the cornea. If there is nothing obvious, check if there is watering or redness of the eyes. Was the pregnancy uneventful or did you have any infection during pregnancy?
Next Steps
Do have it checked either with a local Ophthalmologist preferably a paediatric ophthalmologist.