Luxembourg birth

What if his parents marry later?
How would the legitimation following the mariage be applied to the
Luxembourg Grand Ducal illegitimate child?

edespalais...

Legitimated, it may once even become the grand-duke. All depend of the
constitution. In the states of the House of Austria a child has only
then the capacitas succedend, when conceived after the religious
marriage. One may belong to the House, even be the head of the House,
but one does not have the capacitas succedendi, i.e. one cannot succeed
in the ruling of these states.

Stephen...

Do you really mean "conceived" here, or "born"? For a child born

edespalais...

for

approximately nine months after a marriage, it would be rather difficult for
anyone (other than, perhaps, the parents) to be able to determine whether

edespalais...

why

conception took place before or after the marriage. This is, presumably, why
the date of birth has such importance.

edespalais...

At the time of the fixing of this rule modern techniques did not exist!