Three-year-old A.J. Werner knows why there's a vertical scar running down the center of his chest and the chest of his one-year-old brother, Tyson.
"He knows why he has 'owies,'" the boys' mom, Gina Werner, said. "His heart was broken and they had to go in and fix it. Then when they were done they glued him up."
A.J. stands in the Werners' living room and nods in accord as Gina explains the cause of his scar. He pulls Tyson's shirt up to show his brother's "owie."