Question: Who is Johnny De Mol's maternal grandfather?
Sentence (from "Willeke Alberti"): Willeke Alberti (3 February 1945, Amsterdam, Netherlands) (real name: Willy Albertina Verbrugge) is a Dutch singer and actress, the daughter of entertainer and singer Willy Alberti (1926–1985) and Hendrika Geertruida Kuiper (1921–2011).
Relevant evidence: Yes