Boytwin had really bad conjunctivitis recently, lots of goo from his eye and he looked like he had been punched it was so red and swollen, but the white or his eye was still white.

Girltwin, on the other hand, has a bloodshot eye which I am assured is nothing to do with conjunctivitis, and she must have gotten some dust or something in her eye which has irritated it. I guess it depends on what sort of conjunctivitis they get, and how badly the inside of the eye is irritated by it.