I am due with my first girl on September 15. My sons are C00per and C@mden. Obviously, their names are matchy (both Cs, both six letters, both surnames). It wasn't our intention, but that's how it worked out. To top it off, their intials are also exactly the same. Baby 3.0 does not have to be a C, but if a C works out, we're good with that. This will, in all likelihood, be our final child.
All that said, our first name list looks like this:
Cara (which we have liked since my second pregnancy)
Calista, nn Cali/Callie
Emerine (a surname from my husband's side of the family)
We've liked the name Cara for YEARS, but after too boys Cara doesn't seem "grand" enough ... like we need something that makes more of a statement. Silly, I know. I am also concerned for her always correcting "It's a C, not a K." I like the name Callie but would like a more professional-sounding option for her too. Calliope and Calpurnia are both out, so Calista seems reasonable (and my husband quite likes Calista). We thought we were really on to something with Emerine - it's a surname! it's a family name! it seems sort of familiar because of the popularity of Emma and Emily! BUT I don't like the way it looks. It sounds feminine, but it doesn't look feminine. The only middle name I found that I really like with it is Grace ... but Emerine Grace G1bs0n leaves her with the initials EGG. Nope, not going to work.
For girls, my husband likes "fussy princess" names. Longish, Latin/Greek-rooted name, usually ending in -a or -ah. I generally like German/Hebrew-rooted names (like Chelsea) or fun ones (like Piper). Husband has vetoed both Chelsea and Piper. We like less-popular first names as our last name is quite common and plain.
Other names we've discussed and won't use:
Olivia (too common, Husband obsessed with Olivia the Pig factor)
Malia (I kind of like, Husband does not)
Mariska (both liked but people's reaction was consistently "Marissa?" which I quite dislike)
Carissa (my husband's suggestion that I detest)
Paige (too popular, too short)
Carys (Husband thinks it's weird)
Middle names up for consideration are June, Marie, possibly June-Marie or Junemarie (to hyphenate or not?), maybe Lillian (all family-honoring names).
Personally, I am leanings towards Cara June or Cara June-Marie. My husband is leaning towards Calista but will (in all likelihood) come around to whatever I really want.
Very open to additional name suggestions.
I was immediately leaping on alternate spellings of Emerine that might look more feminine to you when I realized it was a family surname name, which means it loses a lot of impact if we change the spelling. If you do decide to use it, I like Rose as a middle name: Emerine Rose G1bs0n. I think Emerine Paige G1bs0n works well, too.
I know you said you're open to non-C names, but I find I'm drawn to them for you if this is most likely your last child. (If you think it's more than remotely possible you'll have another, I'd be more disinclined to lock you into a C pattern.)
Cara and Calista make me think of Calla: it's almost a perfect in-between of fanciness and length, and you could still use Callie as a nickname.
I think Cadence would fit well with C00per and C@mden.
I like Cecily a lot, and it has six letters just like C00per and C@mden. Cecily Paige G1bs0n, Cecily June G1bs0n, Cecily Marie G1bs0n.
I also like Claire---and again, six letters. Claire June-Marie/Junemarie G1bs0n.
Or Clara. Clara Paige G1bs0n, Clara Junemarie/June-Marie G1bs0n.
Or Claudia. Claudia June/Marie/Paige G1bs0n.
Cleo might appeal to your husband's classical tastes while being fun and non-frilly for yours. Cleo June-Marie/Junemarie G1bs0n.
A name I recently noticed in The Baby Name Wizard is Carling. I like the way it rhymes with Darling. I like that it's similar to names like Carli, for familiarity. It's similar to Cara, but fancier. It's a surname name. And I think it goes well with C00per and C@mden.
Another is Calloway. It has a pretty sound, like Willow, and it gives you the nickname Callie.
Name update! Melissa writes:
We went in a totally different direction than planned.
Everly Juno joined our family on September 8.
We settled on it just days before her arrival and it took a while for it to "feel" like her name, but we're very happy with the name and with her - she's sweet as can be!
While it's not a "C" name, it is an English surname and six letters (just like the boys' names). All three kids have a "J" name as their middle name. There's enough in common to make the sibling set cohesive but she gets to be a little different with her own initial and three syllables :)