From "History of Old Allegheny Township, Westmoreland County, Pennsylvania, From Prehistoric Times to c. 1876" by Rev. Reid W. Stewart, Ph.D., Appendix 39 is Brookland Reformed Presbyterian Church Marriages 1835-1883, from Vol. 2, Records of the Congregation of Brookland, N. Washington and Manchester Marriages 1855-1883, is a marriage date of 09 Mar 1869 John B. Alexander to Jane Euwer.
I do not have this book, just a few pages from it, but my best guess is that Jane is the daughter of Robert and Nancy Euwer. I know nothing of Robert Euwer, his siblings or parents, at this time. From census records, he was born about 1798-1799 in Ireland.
Nancy was also born a Euwer about 1808 and probably in Plum Township, Allegheny County, PA, the daughter of John Euwer and Agnes McMullen. I descend from Nancy's brother, Archibald. Please let me know if you get this message.
Mary Lou