I am trying to find out how to obtain records on my great-great grandmother and her brother. They are believed to Cherokee from Oklahoma, and were taken from their tribe. She is nown by Harriet Minnie Meyers or Minnie Harriet Meyers, and was married to a Richard Yarroll (divorced him)and then married a McDonald. Her brother was known by Albert Meyers. I do not know their real names, but I do have pictures of them. I am hoping fr some suggestions about how to continue, I haven't had any luck. Thanks for any suggestions.