Mo. Rev. Stat. § 429.150: Who construed as owner or proprietor.

Every person, including all cestui que trust, for whose immediate use, enjoyment or benefit any building, erection or improvement shall be made, shall be included by the words "owner or proprietor" thereof under sections 429.010 to 429.340, not excepting such as may be minors over the age of eighteen years, or married women.