Playing favorites with one's children is clearly a moral grey area at best...so why do we do it?
I'm a personality psychologist by training, and particularly well-exposed to heritability research through my alma mater, so I can appreciate the power of genetic variation and individual experience on personality. Sex of the parent may determine the favored sex, and I'd bet that the rarer sex among more than two siblings of different sexes would see some special treatment more often than not too.
What are the primary factors that can contribute towards parental favoritism towards their children, and how can it be avoided and overcome?
Is it ever okay? Even if not, are there relatively good reasons that are particularly worthy of sympathy or difficult to avoid as a parent?
This post is inspired by the question Why do some parents prefer some children more than others?.
Also, on a personal note, I'm not a parent yet myself, but I plan to be, and am leaning toward fathering more than one. I'm an only child, so I have no direct familial experience myself, and limited access to the intimate details of my friends' experiences with their parents and siblings. We're all just reaching the parenting age ourselves, so no one I know personally has had to grapple with favoritism toward their own children either, as far as I know.