Question: Who is Prince Karl Anton August Of Schleswig-Holstein-Sonderburg-Beck's paternal grandfather?
Sentence (from "Peter August, Duke of Schleswig-Holstein-Sonderburg-Beck"): Thus, by the time that Peter August became the head of this cadet branch of the Danish royal dynasty, he was "Duke of Schleswig-Holstein-Sonderburg-Beck" in name only.
Relevant evidence: No