Question: Who is Charles Eugene, 2Nd Duke Of Arenberg's sibling-in-law?
Sentence (from "Philippe Charles d'Arenberg"): He was succeeded by their son, Leopold Philippe d' Arenberg, as the 4th Duke of Arenberg, whose descendants include the current line of the Prince- Dukes d' Arenberg, as well as Empress Elisabeth of Austria and Albert I, King of the Belgians.
Relevant evidence: No