L.R.
Diabetes is linked to glaucoma and other vision issues but I've only heard of its making vision worse, not better. However, DO get that diabetes test ASAP since it is in your family, and in close relatives too.
If you do have diabetes, be sure to contact the American Diabetes Association ASAP. They can really help you both online and through in-person groups to navigate this condition. It's nothing to ignore or mess with. Especially if it turns out you have Type 1 diabetes, be sure also to keep a close eye on your kids and watch for symptoms like thirst, excessive urination, mood swings and even aggressiveness -- all are potential signs of diabetes. (My lovely, gentle and sweet MIL and her wonderful sister both can become downright violent if they are in a serious sugar crash situation, so if a kid who is otherwise fine starts swinging at folks and being belligerent suddenly it actually can be caused by a dangerous blood sugar low!)