What can explain that so few of the christians in america's south, like tenesee, are catholic, barely a quarter despite catholic large families?

What can explain that so few of the christians in america's south, like tenesee, are catholic, barely a quarter despite catholic large families?

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7 mo
tenesee was a good example, 83% are Christians but only 6/83 are catholic! Carolinas and Georgia around ten 10% it seems catholics failed to convince their own children, to follow pope so they became protestants. Now even more catholics are fleeing catholic. See my question why so many leave.
What can explain that so few of the christians in america's south, like tenesee, are catholic, barely a quarter despite catholic large families?
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