Some of Archduke Rudolf (b. 1950) of Austria's children have been ordained into religious orders. I know Johannes (b. 1981) has been ordained as a priest, and Thomas (b. 1983) and Joseph (b. 1991) and their sister Marie-des-Neiges (b. 1986) have taken religious vows.
There are eight siblings in all, and only two, the oldest, Carl Christian, and the sixth, Franz, are married. So two children married, four in religious orders, and two, Priscilla and Michael, who are unmarried.
Here are a couple articles about Johannes: https://www.tagesanzeiger...tzt-moench/story/29486147https://www.pointdevue.fr...annes-dautriche_6227.html
As I read through this thread, there is something profoundly moving and meaningful, when a grown man decides to turn his back on the secular world & devote themselves to the good of their fellow men, i.e. Johannes, but when one reads of a four year old daughter of a king taking vows back in the 13th century (!!). It must never be that way again.