Grietje was married to Johannes Postma, born circa 1866, bricklayer.
From this marriage:
1 : Willem Postma, born in Harlingen on April 20, 1898, coppersmith.
Willem was married in Harlingen on September 5, 1927, at the age of 29 to Wiepkje de Groot (aged 24 years), born in Harlingen on April 10, 1903, daughter of Tjerk de Groot and Anna Kwast.