Go
here. Mormons "seal" those who died outside their faith into their faith through "Temple Work", although the term includes other "rites" as well. And as I understand it, it's not limited to one's family (as you imply with your "Founding Fathers" remark). It's been decades since I was somewhat understanding of all this so my memory may be somewhat off. Perhaps this link will help. Better yet, consult a Mormon.