When Melissa McCann (left) suffered a stroke in 2007, her twin sister, Terry Blanchard, helped her make a full recovery. McCann is now back to work as a flight nurse with Life Flight at the Eastern Maine Medical Center in Bangor.
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ATLANTIC CITY, NJ - JULY 8: The roulette wheel spins at Caesars Atlantic City July 8, 2006 in Atlantic City, New Jersey. Caesars, along with Atlantic City's 11 other casinos reopend this morning after they were forced to close their gambling floors for the first time in their 28-year history due to the New Jersey state budget impasse. (Photo by William Thomas Cain/Getty Images)
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Maribel Ramos, 13, has both sickle cell disease and an abnormality of blood vessels called moyamoya. Both put her at risk of stroke, and, together, they add up to a 95 percent chance of a major stroke.