Account of the marriage of a Clara B. Stackhouse to George B. Reimensnyder in 1887 in Philadelphia and birth of a child in 1889; another source then has Clara dying April 16 1896. Very well may be the Clara B. Stackhouse who composed the one work for piano- or rather one movement of one work for piano - LoC seems to have. OTOH there's also a record of a Clara Troth Stackhouse (Spenser) (1862-1951) marrying a composer Willard Spenser in 1886 - less likely though, obviously...