my son had a upper lid ptosis surgery a month ago, is it healing normally? (photos)

It looks like your son had a congenital ptosis repair surgery.  This involves small incisions above the brow to bury the substance that is elevating the lid.  On one picture you can see that he has a small hypertrophic scar.  Some silicone cream or steroid cream should help with that.  On the other side there is some inflammation at the wounds - with loss of pigment.  Pigment loss is not uncommon in darker skinned individuals.  There may be some mild infection here too, so see your surgeon.

Pictures show retained stiches that causing inflammation. Please see your son's surgeon for removal. The inflammation is due to the retained stitches.