Jacobus married Anna Maria Mertens on 28 September 1780 in Kerkrade, Limburg, Nederland. Anna was born on 28 February 1755 in Kerkrade, Limburg, Nederland; died on 12 January 1796 in Drievogel, Kerkrade, Limburg, Nederland. [Group Sheet] [Family Chart]

1. Balduinus Aretz was born on 04 October 1781 in Kerkrade, Limburg, Nederland; died on 21 August 1783 in Kerkrade, Limburg, Nederland.
2. Maria Gertrudis Aretz was born on 09 January 1784 in Kerkrade, Limburg, Nederland; died in August 1843 in Schinnen, Limburg, Nederland.
3. Wernerus Aretz was born on 25 July 1786 in Kerkrade, Limburg, Nederland; died in Date unknown.
4. Maria Catharina Aretz was born on 18 February 1789 in Kerkrade, Limburg, Nederland; died in Date unknown.
5. Maria Margaretha Aretz was born on 29 March 1792 in Kerkrade, Limburg, Nederland; died on 28 August 1793 in Kerkrade, Limburg, Nederland.
6. Augustinus Josephus Aretz was born on 18 July 1794 in Kerkrade, Limburg, Nederland; died on 07 November 1795 in Kerkrade, Limburg, Nederland.