It might be simpler to compare less sacred values (how many sparrows is a dog worth? How many dogs is a chimp worth?) building up to something greater. Unfortunately, Kawoomba seems to be under the impression that nothing could possibly be worth the life of his family. Not sparrows, not humans, not genocides-prevented.
That is so. Why unfortunately? Also, why "under the impression"? If you were to tell me some of your terminal values, I'd give you the courtesy of assuming you are telling the truth as you subjectively perceive it (you have privileged access to your values, and at least concerning your conscious values, subjective is objective).
I get it that you hold nothing on Earth more sacred than a hypothetical sufficiently high number of sparrows, we differ on that. It is not a question of epistemic beliefs about the world state, of creating a better match...
Happy New Year! Here's the latest and greatest installment of rationality quotes. Remember: