Totally agree. The Quiverful belief is always stated in the same terms as the Catholic beliefs, that God will bless you with however many kids you're supposed to have, and that intervening in that in any way is wrong. But families like this ARE intervening, just in the other direction.
If they were just letting their fertility go along its natural course, they would have probably half the kids they do now. I've done a lot of genealogical research, and from what I've seen, having families of 9 and 10 kids wasn't uncommon in the days before chemical birth control...but having families of 19 and 20 kids certainly WAS.
IMO, they are just as controlling of "God's plan" for their lives as anyone using birth control, it's just that they have the opposite goal.
Stopping breastfeeding early (and probably starting to time ovulation again) in order to get pregnant again so quickly after giving birth is just as deliberate and artificial as taking a pill or putting on a condom.
(At least, that's my child-free, non-Christian opinion, anyway!

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