Bonnich married Cathrine Marie Schmidt on 17 May 1898 in Bjolderup Kirke, Bjolderup Sogn, Rise Herred, Åbenrå Amt. Cathrine (daughter of Carsten Thomsen Schmidt and Cathrine Marie Nielsen) was born on 6 Jan 1877 in Smedager, Bjolderup Sogn, Rise Herred, Åbenrå Amt; died on 20 Sep 1948 in Stemmild, Burkal Sogn, Slogs Herred, Tønder Amt; was buried on 24 Sep 1948 in Burkal Kirkegård, Burkal Sogn, Slogs Herred, Tønder Amt. [Group Sheet] [Family Chart]

1. Andreas Boysen Bonnichsen was born on 2 Mar 1899 in Bjerndrup, Kliplev Sogn, Lundtoft Herred, Åbenrå Amt; died on 3 Jul 1984 in Stemmild, Burkal Sogn, Slogs Herred, Tønder Amt; was buried in 1984 in Burkal Kirkegård, Burkal Sogn, Slogs Herred, Tønder Amt.
2. Carsten Schmidt Bonnichsen was born on 3 Apr 1902 in Stemmild Mark, Burkal Sogn, Slogs Herred, Tønder Amt; was christened on 27 Apr 1902 in i hjemmet/at home.
3. Oskar Leonhard Bonnichsen was born on 3 Jun 1917 in Stemmild Mark, Burkal Sogn, Slogs Herred, Tønder Amt; was christened on 23 Jun 1917 in i hjemmet/at home; died on 28 Jan 1943 in Kommune, Russia.