Kim, you may have already found the Missouri Death Certificates that are available online for the years 1910-1964. (Example: Mo. death cert .# 18242, Stone Co., 1936, for Elizabeth M. Long)
Google "Missouri digital heritage" and "death certificates."
You may have found the will for William Long (wife Eliz. M., 7 sons, 2 daughters) written 20 Feb. 1895 and probate 15 Mar 1898, p. 231. Index to Wills and Administrations of Stone County. My Long family is from Miller County.