Thank you so much!! Well, it looks like I have dug into every possibility to find this "blackfoot indian". My grandfather says it's from his Dad's side (DeHaven, Carl C. DeHaven whose father was Charles Grantham DeHaven), but his grandmother was Sarah Luttrell and she doesn't point to being blackfoot and now my grandfather's mother's side does not as well.
My grandfather, John V. DeHaven, is 89 years old and all of his life he has talked about this blackfoot indian. He says its from his dad's side, the rest of the family says its from his mom's side. I was hoping to get some type of "proof" for him, but it seems that won' t be able to happen.
Thanks again for your help!