My middle name is
Cecelia because my grandmother's name is
Cecelia. I'll name one of my daughter's with a middle of
Cecelia.
Honestly though, if it weren't passed through my family with that spelling, I would think that
Cecilia was the better name. I think St.
Cecilia gives it the authority as the "correct" spelling.
As far as nns, I like
Celia and
Cissy. I don't care for CiCi very much. My grandmother goes by C.C. because her last name was
Casper.