Matthys Janse had two sons, one named Jan, who afterward assumed the name of Jansen and became the progenitor of that family. The other son, named Matthys, assumed the name of Van Keuren, and is the ancestor of that family.
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His wife was Margaret Hendricks, and they had four children, one of whom was Jan Matthysen, who, as above stated, assumed the name of Jansen. He married, September 28th, 1667, Magdalina, daughter of Matthys Blanshan, and became the ancestor of some of the Jansen families.