I understand about the middle initial, but have seen many name changes that some people made over the years. Some of the most confusing were where nicknames were used. You would know it to be the same person since they were the right age, in the same family and the same county.
Found this marriage record and it may be for Milderedhttp://grenada.sandysfamilytree.com/marriages-bookb
Grenada Co Ms
Book B, p230..Ansel Miles..M. A. Kelly..May 30, 1882
Good luck in your search.