Margaret Your info sounds right, indeed.Your husband's great grandmother, Mary Ann Shier, married a George Jacob St. John (if my info's right), who's family later on down the line figures prominently into my wife's lineage (as do Switzer's).
I believe you are correct in assessing that my wife is descended from Charles Christopher Shier, and your husband from Nicholas, the two of them brothers.You are aware, I'm sure, of their father, I have as Adam Shier, b. 1674?
All somewhat complicated, but very fascinating, nonetheless. Robin