Over the past 20+ years, I've used several computers and several different family tree programs. I am convinced that information has been lost when I transfer files from one program to the next.
Anyway, I have scant notes regarding Surrilda "Mourlon" (born abt. 1836 in Illinois) being the daughter of Elizabeth Pennington, but not a single source of any kind attached to it (possibly lost by computer). I also note that many people are now calling her "Rilda Clark" in posted family trees, but that clearly is not correct. I know I've discussed this with other cousins met through this board, and perhaps someone can help me out with an actual source.
In the 1860 census, Surrilda is married to George T. Watters, and their household includes 13 year-old Martha Pennington. The previous household is that of John Brooks Clark and his wife, Elizabeth Pennington Clark, her alleged mother. Two households below is that of Thomas Howard Morlan, 2 years older than Surrilda. The headstone for Elizabeth Pennington Clark states she was born in 1819; if accurate, she would have been fairly young when Surrilda was born, and perhaps too young to be the mother of Thomas. However, these dates are commonly wrong.
The reason I bring this up now is that I find Surrilda remarried to John A. Wilson (sometime between 1860 and 1870). I have also found that John A. Wilson married Mary "Alice" Clark, daughter of John Brooks Clark and Elizabeth Pennington, in 1903. John A. Wilson died in 1904, and Alice in 1919. Many people list (as I have for over 20 years) that "Alice Clark" married "Crooks?" and "Wilson?", and died "about 1919". That's all been proven now with available records. So the question remains - did John A. Wilson marry the widowed half-sister of his late wife, Surrilda? If Elizabeth Pennington was their mother, then the answer is "yes".