There are a number of reasons. Some babies may appear to have a squint that is not a true squint. It is called 'epicanthus' and is caused by folds of skin on a wide nose. Light rays fall beyond the retina. Long sight corrected with spectacle lens.
Light rays fall on the retina.
Then the optometrist measures what lens is needed by shining a special light into the eye and seeing how its reflection is changed. Yes unless advised otherwise. In the Visual Assessment Department we specialise in children's care and hold a good selection of frames at competitive prices. We ensure you are able to have a pair of glasses without additional payment. However, you may choose a more expensive frame and prefer to pay the difference.