This is interesting, because the guy who bought the Rothschild hunting estate in Austria was sold to PrinzhornHolding Company; Thomas Prinzhorn adopted the son of Karel Schwarzenberg, who was at one time the head of the Schwarzenberg family. Why the head of the house of Habsburg would let his son be adopted by someone else is hard to figure, and I couldn't find anymore information on it.
https:// www.bloomberg.com/news/articles/2018-01-31/rothschilds-sell-austrian-hunting-estate-in-a-historic-deal
https:// en.wikipedia.org/wiki/Thomas_Prinzhorn
https:// en.wikipedia.org/wiki/Karel_Schwarzenberg