On 14 Jul 1922 when Roelof was 27, he married Zwaantje Wijnholds (66392) , daughter of Hindrik Wijnholds (66029) (31 May 1851-25 Sep 1930) & Hindertien Pagters (64211) (24 Sep 1854-18 Feb 1956), in Emmen, Drenthe.538 Born on 21 Jul 1891 in Nieuw Dordrecht (Emmen), Drenthe.538 Zwaantje died in Emmen, Drenthe, on 5 Feb 1960; she was 68.

Roelof and Zwaantje were second cousins; their paternal grandfathers were brothers.