My grandparents are buried at Cedar Grove also and it seems that back in the day there was a fire that burned all the cemetery records, families had to tell them who was buried there in order for them to create a new list, my grandmother died in 1940 and didn't have a headstone until the 1960's when my father and my uncles carved one and put it down there, my cousin's mother was married to a Gibson, Wray Gibson...if that rings a bell she might have some info on it...