If my parents have health insurance, does that mean they don't pay a cent?

So I was hospitalized recently for an eating disorder. I was in treatment for just under a month, and my parents said that insurance covered the whole thing. My family has reliable health insurance. I was just wondering if that meant that my parents didn't even have to pay a penny for treatment, or what? How much do people with insurance still have to pay? Thank you!
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well it depends on what type of insurance you have and what type of plan you have with that insurance some cover the whole bill but thats the really expensive ones and others pay 10-90 percent of the bill...the more you pay for your health insurance the more they cover your bill
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