Wilmer married Lulu May Sanford, daughter of John Gano Sanford and Laura Belle McDONALD, on 28 Dec 1898 in Auxvasse, Calloway Co., MO. (Lulu May Sanford was born on 1 Apr 1876 in Mexico, Audrain Co., MO and died on 11 Jan 1960 in Auxvasse, Calloway Co., MO.)
