But now toddler Maisie Harris - whose brain does not tell her body to breathe - has been able to go home for the first time. And it's all thanks to advances in technology.
Now nearly three-years-old, Maisie suffers from congenital central hypoventilation syndrome' (CCHS), also known as "Ondine's Curse" - a rare condition, which means her brain does not tell her body to breathe.
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