Hi. I know nothing about these particular families, but is their any chance Galbreth could be a married name? As in, Sarah Mills married a Galbreth was widowed and then married her cousin? I'm just throwing the idea out there because I've had weird things like that turn up in my own research. Sometimes my grandpa will tell me something about how a person is related, but when I go searching, the information doesn't seem to match up with his story. Upon further digging, I find that a name is a married name or the siblings he mentions were actually half-siblings with a different surname. My grandpa has actually been right every time, even when I find records that at first seem to contradict what he tells me. It might be something to look into anyway.