In Minnesota How old are u covered for health insurance?

on a Parents work-provided health plan how old does your child have to be to be covered is it after 18 they need to be in school to be covered? or are they covered until 21?
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....under the new health care if it passes your child can be insured up to age 26. Under the current plan.. you are carried under most insurances until 18 but if you are in college that lasts until 21 years of age.
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