Just in case you haven't yet found where they are buried, here is what I know. The burial site for Thomas is unknown. His obit states he was buried in Salem Cemetery. The only Salem Cemetery known to be in Washington Co is a Lutheran cemetery, and there is no data on Thomas being buried there. Catherine is buried in the Proctor Cemetery, Comanche Co. Her son Thomas Samuel is also buried there. James Monroe is buried in the Kurten Cemetery in Brazos County...that is just outside College Station.