I have three Hennessy girls, Bridget b. 1829, Mary b. 1833, and Anne b. 1835, who claimed to be sisters. All were in Bear Creek, WI by 1860 and married. Various records name their parents as either Bridget, Mary, John, or Thomas. We do not know what county they were from. Does this match your Hennessys (also spelled Henchy or Hanshey)?