how does health insurance work in this aspect? is it more expensive for a company to insure a family of 4 than

a family of 3? does the cost go up per insured or is there just family coverage and individual?
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Employee only Employee and spouse Employee and child (you and all of your children) Employee and family (you, spouse and all of your children) It doesn't matter if you have 1 child or 6. The price is still the same. (Anthem)
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