Who Is Martha Casebeer?

In 2008 Janice Stemler of Glendale, AZ, addressed a letter to the Postmaster of Carlisle, IA. She wanted someone to go to the cemetery and read a stone. Ms. Stemler wanted to know the birth year for Martha Felton Casebeer, as well as her death month and date.
She knew that Martha had been married to Solomon, and that he is buried in northwest Missouri. Ms. Stemler included the information that the Casebeer’s came from Lima, Ohio and brought their daughter, also named Martha, who was born on January 22, 1858.
Young Martha was a small child when they moved to Iowa. Mr. Tim Freeman gave the letter to Carole Gates because he knew she was a member of the Historical Society. She passed it on to Melody Kirk, who proceeded to do some searching at the Carlisle library.
Melody knew that the late Joan Schooler had identified and organized the plots in the cemetery, and Melody was able to find the headstone because of Joan’s work. Melody took pictures of the headstones and wrote to Ms. Stemler. An interesting side story arises, because there are TWO headstones for Martha Casebeer.
One is the original, but the second, and much more recent stone, had also been placed there, and it had the requested information plainly carved. The head stones can be seen from Fifth Street. If you line yourself up with the white shed, and look to your left you can see the very distinctive shape.
Every answer opens up several more questions. The most obvious one being, why is Solomon buried so far from his wife, and also, who placed the second stone? It must have been a family member who wanted to be sure that Martha was remembered..