What shows that Mary McLeod married Edward Smith in 1864?
Sarah Smith's maternal grandparents are John McLeod 1810-1883 and his wife Sarah McLeod 1821-1884. Sarah McLeod's maiden name was McLeod.
If Mary died in 1868 at 27 years she would have been born about 1841. However in MacLeod/McLeod files the Mary of this McLeod family born about that year was married to Joseph Obleman. I'll go back to McLeod census.

Anne