This is going to be a short post, indeed so short, you would miss it if you blinked.
I have repeatedly asserted that there is only thing that defines marriage – the potential product of a male-female physical union is given the tag of legitimacy, if and only if the two protagonists are married. This is a necessary and sufficient condition.
Take this one step further and let us not question biology – accept that a physical union of a man and a woman is required to produce a human being (let us leave aside in vitro and other stuff aside). Then, a child born not in holy (howsoever defined) matrimony is de facto illegitimate.
This, to my mind, is a violation of human rights, of the infant. The only way to correct it is to legitimize EVERY human infant, no matter the circumstances of his or her birth. You may say this is already so legally. Whatever may be de jure, it should be made de facto, society should downgrade the institution of marriage at least to the extent that an infant’s right as a human is not willy-nilly abrogated.