I have three kids, ages 8, 11, and 13. This morning, all three of them complain of sore throats. I looked in their mouths w/a flashlight, one has a thick yellowish/white stripe down the center of the back of his throat, one has a blood red/purple stripe down the center of the back of her throat, and one has a very red throat (all over, including his tonsils). I've seen white patches with strep, but never this "stripe". Could this be strep? If so, can strep resolve itself without antibiotics?