I'm not sure, Kevin.

It could be there were two wives, but you'd have to check on dates to see if the two names "overlap" in time to help sort that one.

Also, Nellie might well be a nick-name. Couple of examples: One of my cousins has a grandmother who was never called anything but Dina (pronounced Dinah - like the one blowing the horn). Her real birth name was Beulah Mae. My father had close cousins who had never heard him called anything in their whole lives except "Punch". They were all in their 70s when some of these cousins found out his real name was Orval. His mother had called him "Buster" the first few years of his life.

There's no tellin' why they called her Nellie, but there's a good chance they are one and the same person.

Regards,
Penny