It's hard enough for two parents working together to protect their kids from the parasites, but when one parent tries to turn the state against the other one, it becomes way more difficult.
They just put a mom in jail here in Michigan for refusing to vaccinate her kid. The dad wanted to vaccinate, court ordered it, mom refused or delayed, and they sent her to jail. The only law the domestic courts follow is 'I am the law" meaning they unilaterally decide what's best for the child and issue orders accordingly.
I'm pretty good at following the law. Not so good at following orders. That's the difference between a citizen and a slave.