I’m 5 weeks from my due date and still struggling with a name. My husband loves the nickname [name_u]Charlie[/name_u] for a girl, but I fear [name_f]Charlotte[/name_f] is way too popular. What do you think of the name [name_f]Caroline[/name_f] [name_f]Charlotte[/name_f]? Could she still go by [name_u]Charlie[/name_u] if [name_f]Charlotte[/name_f] is her middle name, or is that weird? Is it too much like [name_f]Charlotte[/name_f], [name_u]North[/name_u] [name_f]Carolina[/name_f]?
Unless of course you have a problem personally with just [name_u]Charlie[/name_u], using it by itself would be just fine. I know a girl [name_u]Charlie[/name_u], who’s full name is [name_u]Charlie[/name_u].
[name_f]Caroline[/name_f] [name_f]Charlotte[/name_f] is nice, but they look a little similar. If you still like [name_f]Caroline[/name_f], you could use [name_f]Carly[/name_f]/[name_f]Carlie[/name_f] as a substitute for [name_u]Charlie[/name_u]. As for [name_f]Charlotte[/name_f], [name_u]North[/name_u] [name_f]Carolina[/name_f], I’ve never heard of it, although I am still a student living in [name_f]Canada[/name_f], so I don’t know much about geography in [name_u]America[/name_u] to begin with.
Hmm…both names are on my list too; however, [name_f]Caroline[/name_f] and [name_f]Charlotte[/name_f] are both feminine derivatives of [name_m]Charles[/name_m]—[name_f]Charlotte[/name_f] from the English form, and [name_f]Caroline[/name_f] from the Latin form ([name_m]Carolus[/name_m]). To me, using them together sounds a bit odd, like naming someone [name_m]Johnny[/name_m] [name_m]Jack[/name_m].
For the same reason, I see [name_u]Charlie[/name_u] as a viable nickname for [name_f]Caroline[/name_f].
I love both names and the combo sounds nice but I feel like it’s a bit weird to use two variations/feminizations of the same name. Maybe [name_f]Emmeline[/name_f] [name_f]Charlotte[/name_f] or [name_f]Coraline[/name_f] [name_f]Charlotte[/name_f] instead? But if you want to use [name_u]Charlie[/name_u] as the nickname, I would personally just use [name_f]Charlotte[/name_f] as the first. I don’t see the point in having a different first name on paper just so it’s less popular.
I agree with everyone. They’re a little similar and indeed derived from the same name, so personally I wouldn’t use them together.
While yes, the name [name_f]Charlotte[/name_f] is becoming increasingly popular, I don’t think it’s TOO popular (yet). Honestly, I say go for [name_f]Charlotte[/name_f] as the FN, especially since your husband loves it and is already thinking of the cutest nickname! [name_m]How[/name_m] sweet. 
[name_f]Edit[/name_f]: Oh, and I think [name_f]Charlotte[/name_f] [name_f]Caroline[/name_f] sounds better than [name_f]Caroline[/name_f] [name_f]Charlotte[/name_f].