Sneezy kittens should always be seen by a vet. At minimum a triple snap test should be performed on any kittens during their first vet visit to ensure that the kitten doesn’t have FIV or FeLV which are both life threatening. If negative for both viruses, the kitten may have a upper respiratory infection which is fairly common at that age but still needs antibiotics to treat especially since they are babies and don’t have a very strong immune system. If left untreated in a kitten, URIs can advance to pneumonia and the buildup of discharge in the eye could cause harmful bacterial infections. In the meantime you can provide some slight relief by running a hot shower while the kitten is in the bathroom. The steam will have a nebulizing effect and clear those airways a bit. Best of luck