Carl,
Carla and
Karel (Dutch version of
Carl) and also
Karl, are family names for me, so I like them a lot :-D
Carla &
Matilda is a great sib set.
I'm not fond of
Carlie as
Carly and variants were trendy in the 80s, so I've known far too many ditsy bimbo girls named
Carly, or even worse, Carli (of course, the grand prize for trashiness goes to the parents of a lass named Karli-Dee!). But as an occasional nickname for the graceful
Carla it wouldn't be so bad (particularly if you spell it
Carlie, which looks nicknamey).
:-)