http://akevoth.org/genealogy/ndbcore/3064.htm

Abraham Barend Koekkoek, birth 17 Dec 1824 Groningen, Groningen, Nederland, died 26 Jul 1908 Groningen, Groningen, Nederland, son of Barend or Barent Benjamin Abraham Koekoek\Koekkoek and Heintje Jacobs

Married 19 Aug 1860 Groningen, Groningen, Nederland to:

Carolina or Grietje de Swaan, birth 18 Jul 1834 Groningen, Groningen, Nederland, died 16 Apr 1917 Groningen, Groningen, Nederland, daughter of Benedictus Salomon de Swaan\Zwaan and Jetta or Jette or Judik Arons\Arends

1) Heintje Koekkoek, birth 5 Jul 1858 Groningen, Groningen, Nederland, died 31 Jan 1907 Assen, Drenthe, Nederland Married 22 Apr 1877 Groningen, Groningen, Nederland to: Salomon Swartenberg, birth 26 Feb 1853 Westerbork, Drenthe, Nederland, died 25 Mar 1923 Assen, Drenthe, Nederland, son of Berend Levie Swartenberg and Roosje van Gelder

2) Jette Koekkoek, birth 15 Sep 1860 Groningen, Groningen, Nederland, died 22 Sep 1860 Groningen, Groningen, Nederland

3) Keetje Koekkoek, birth 24 Aug 1861 Groningen, Groningen, Nederland, died 23 Jul 1943 Sobibor, Biala Podleska, Polen Married 7 Nov 1880 Groningen, Groningen, Nederland to: Philip van Gelder, birth 9 Jul 1855 Kampen, Overijssel, Nederland, died 23 Nov 1931 Groningen, Groningen, Nederland, son of Joseph Levie van Gelder and Eva Levie Knoek

4) Barend Koekkoek, birth 21 Oct 1863 Groningen, Groningen, Nederland, died 28 Oct 1863 Groningen, Groningen, Nederland

5) Jette Koekkoek, birth 23 Sep 1864 Groningen, Groningen, Nederland, died 26 Oct 1942 Auschwitz, Katowice, Polen Married 6 May 1894 Groningen, Groningen, Nederland to: Jozef Graveur, birth 2 Oct 1867 Groningen, Groningen, Nederland, died 29 Oct 1936 Groningen, Groningen, Nederland, son of Salomon Graveur and Engeltje Simmeren

6) Barend Koekkoek, birth 23 Jun 1866 Groningen, Groningen, Nederland, died 7 Aug 1938 Groningen, Groningen, Nederland Married 17 Jun 1894 Groningen, Groningen, Nederland to: Eva van Gelder, birth 26 Mar 1869 Groningen, Groningen, Nederland, died 2 Jul 1904 Groningen, Groningen, Nederland, daughter of Philip Lazarus van Gelder and Matta Karseboom

7) Philippus Koekkoek, birth 9 Jan 1868 Groningen, Groningen, Nederland, died 26 Dec 1930 Groningen, Groningen, Nederland Married 4 Feb 1900 Groningen, Groningen, Nederland to: Betje van Gelder, birth 19 Jan 1874 Groningen, Groningen, Nederland, died 14 May 1943 Sobibor, Biala Podleska, Polen, daughter of Philip Lazarus van Gelder and Matta Karseboom

8) Levi Koekkoek, birth 26 Aug 1869 Groningen, Groningen, Nederland, died 30 Nov 1873 Groningen, Groningen, Nederland

9) Truda Koekkoek, birth 23 Oct 1871 Groningen, Groningen, Nederland

10) Mietje Koekkoek, birth 21 Dec 1873 Groningen, Groningen, Nederland, died 21 May 1943 Sobibor, Biala Podleska, Polen Married 23 Jul 1899 Groningen, Groningen, Nederland to: Sander Velleman, birth 12 Jan 1874 Groningen, Groningen, Nederland, died 21 May 1943 Sobibor, Biala Podleska, Polen, son of Jacob Benjamin Velleman and Klaartje Druijf

11) Betje Koekkoek, birth 28 Feb 1875 Groningen, Groningen, Nederland, died 8 Mar 1875 Groningen, Groningen, Nederland

12) Louis Koekkoek, birth 28 Oct 1876 Groningen, Groningen, Nederland