Sadie vs Giselle "Gigi"

Okay, so I really like the name [name_f]Sadie[/name_f], but I used it on another character and I’d prefer for my characters to have a nickname. Then again, I love the hissing sound it has to it since my book is kind of like a mystery/action-adventure. I also like how graceful [name_f]Giselle[/name_f] is(it reminds me of the ballet) and I’ve always liked the nickname [name_f]Gigi[/name_f], but I also love the hiss to [name_f]Sadie[/name_f], which makes her sound tough. What do y’all think?

I personally love the name [name_f]Sadie[/name_f], but from your description I think [name_f]Giselle[/name_f] ‘[name_f]Gigi[/name_f]’ is the way to go!