Mo. Rev. Stat. § 456.10-1007
If the happening of an event, including marriage, divorce, performance of educational requirements, or death, affects the administration or distribution of a trust, a trustee who has exercised reasonable care to ascertain the happening of the event is not liable for a loss resulting from the trustee's lack of knowledge.
(L. 2004 H.B. 1511)
Effective 1-01-05, see § 456.11-1104