Ethe Lane Ramsowar

My Dad’s Grandmother was Tsalagi. She is on the Dawes. But I keep getting a form letter from the Cherokee Nation saying they want her birth certificate as confirmation. I don’t have it and my Dad has passed for which his wife (my step Mom) got rid of his boxes of paperwork. Her maiden name has several different spellings which has made the search more difficult. Her married Name is Ethel Lane and her maiden name is Ramsowar (sp?) They moved to Oregon after my grandmother was born in Oklahoma. Ethel’s Husband also had Tsalagi heritage from Kansas who moved to Oklahoma to meet Ethel. But his name is pretty common John Lane. The census lists him and his father (also John Lane) as Mulatto. which was common for Native mixed people back then. I’m looking for the Ramsowars and any way to find (if there ever was one) a birth certificate for my Great Grandma Ethel Lane born in Texas but lived in Oklahoma.