Hmmm... It's not much to go on, but here are a few options.
Cecilia, by the way, means "blind". (Cecil is typically the male form)
NAMES THAT MEAN CHEERFUL
Alair, Alanna, Alyanna, Hillary, Ilaria, Bonnie
NAMES THAT MEAN JOY
Abbie, Abigail, Chara
NAMES THAT MEAN FLOWER
Azalea, Clover, Camellia, Daisy, Fleur, Jasmin, Lilly, Lilliana
NAMES THAT MEAN SUNSHINE
Solana (didn't see other in my initial search, but I'm sure there's others)
NAMES THAT MEAN FRIEND
Dakota, Winnie, Connolly
Obviously there's countless others, but that is a few options. This is how I often like to name my original characters for my projects. For me, it feels more meaningful when I pick something that is associated with the character's personality.
I would think about what makes your character. Decide on her personality traits, her history, her likes and dislikes. This will help you get to know your character and what name would best represent.