Birds of a Feather Sacrifice Together

There are only two birds used in sacrifice and always the Tor is mentioned before the bnei yonah. The only exception is by giving birth (in Tazria) where ben yonah is before the tor and even there just when the woman is bringing only one bird.

The quality of the tor as understood by the rabbis is -it mates for life and will not seek out another mate if its dies. The yonah will still return to care for its young if the nest is disturbed (by humans?) They both display exceptional loyalty. That is why these 2 are the only ones allowed as sacrifice.

For all other bird sacrifices, there are 2 birds except by woman who gives birth. She brings a keves and one bird. The torah is showing compassion to the Tor by not making it the bird of choice here because it will end up leaving a mate all alone. (By other sacrifices 2 tors are taken, ostensibly the mated pair).

I told the rabbi that continuing that thought, the yonah goes first to teach the woman who gave birth that no matter what messes with her 'roost' she needs to be there to protect and raise her kids.

With regard to the tor being the lesser of the choices here: In the past infant mortality was high. If the mother takes the attitude of the tor, that everything ends with the loss of the significant other, the mother may choose not to move on nor have other children. The loss should not be an end-all like it is by the tor. So choose to support your family rather than withdrawing from life.