Nathan Wijnberg married Elisabeth Evalina Overste. The chuppah was performed by Chief Rabbi J. Vredenburg of Arnhem's Dutch-Jewish Congregation on 12 August 1925.
On 6 April 1927 their daughter Betty Johanna was born in Groningen and their son Martin Siegfried, also in Groningen, was born on 5 February 1929. Martin Siegfried was circumcised by the mohel S.B. Nathans in Groningen on 28 February 1929. On 24 April 1933 their son Nico Albert was born in Lochem. The following documents remain from this family:
- a certificate of registration with the National Militia dated 5 January 1900
- proof of admission to the lessons of the Second Drill Period, dated 26 February 1900; Nathan Wijnberg was allowed to attend the second drill period after having attended basic training in Baflo in the winter of 1899-1900.
- a summons dated 24 September 1900 for the draw for the National Militia
- the text of the agreement dated 1 May 1901 between Nathan Wijnberg, a merchant's clerk, residing in Winsum, and Nathan Albert de Vries, a merchant, residing in Groningen, in which Nathan Wijnberg purchased the firm registered as Weduwe N.I. de Vries, registered in Winsum.
- a notice dated 20 August 1917 to register for the Landstorm.
- a summons dated 24 August 1917 for the Landstorm inspection.
- a slip of registration to do business as a hide salter under the company name Weduwe N.I. de Vries.
- The founding deed of N.V. Wijnberg‘s Wol- en Huidenhandel in Groningen.
- A passport with a photograph registered to Nathan Wijnberg.
Jewish Historical Museum, Documents 8129- 8131, 8134-8137, 8145, 8169