I really like the idea of using [name_f]Autumn[/name_f]! It makes sense to honor your grandpa and it’s a warm, cosy, crunchy feeling name.
I think it’s a hard one to nickname and the Autumns I’ve met have always been “just” [name_f]Autumn[/name_f] but mayyyybe something like Toto, [name_f]Ami[/name_f], [name_f]Tommie[/name_f], [name_f]Mamie[/name_f], [name_f]Umi[/name_f], Ozzie…