If Zoe Dewaghe wants ice cream for breakfast, she gets ice cream for breakfast. There's a different set of rules for her younger brother, Zach: He gets oatmeal instead. That's because five-year-old Zoe Dewaghe has a rare genetic disease called Sanfilippo syndrome. She'll gradually lose the ability to speak, to move, to recognize her surroundings. Most patients don't live into adulthood. "Once we found out what was wrong with her, we were like, 'You can eat whatever the heck you want,'" Zoe's mother, Liz, said ruefully. "Because pretty soon, you won't be able to eat." There's no approved treatment for Sanfilippo syndrome.