Nearly a year after suffering a mini stroke, Frankie Muniz had a second, the Los Angeles Times reports. "Almost a year to the day, I experienced another mini stroke. Hopefully that will be the last. Miserable," tweeted Muniz, who turns 28 next week, on Monday. He hasn't released any further details, and doctors never did figure out what caused his first mini stroke. (The mini version can act as a warning of what could come: a full-blown stroke, notes the Times.) Muniz says he has never had a drink or done drugs, but has admitted to having a poor diet.