people struggling with being unequally yoked with an unbelieving spouse
Stopped clock: a common worldview can help to maintain a marriage. However, some couples don’t have any issue with such differences: even the Catholic church celebrate marriages of its members with non-baptised spouses, only caring about a mere promise to raise Catholic children.
And even if the worldview was the same, life happens: som years ago, I read in La Croix about a couple where initially both spouses were Catholic but the husband lost the faith in 1968, and this couple still was together when the article was published.
there are situations where children, raised in Christian homes, have fallen away from their faith
That’s free will: parents only can provide their children the educational bricks needed to grow but, after, your children do what they want with. And the reverse happens: there’s plenty of converts from non-Christian or non-religious homes.
Look at these businessmen whose children bankrupt their companies (so much that the “third generation curse” seems to have created saying around the world), these honest parents raising criminals or these intellectuals raising cretins.