My family's ancestor Arend Jakobs Brugman, b. 1836 in Tergast, Ostfriesland, Germany, had two sisters Gebke, b. 1827 and Elizabeth, b. 1828. It is possible that Gebke married John Reufsaat in Stephenson Co., Ill ca 1860 and that Elizabeth married E. M. Knock also in Stephenson Co., Ill ca 1865. However, I have been unable to find any primary source material to confirm that these two women are in fact siblings and that they are sisters of Arend.
Does anyone have any source material one way or the other?