While Julia was historically more common, these days I am much more likely to run into a Natalie - especially one born any time from the late 80s to now. So for me, that would be the deciding factor in choosing Julia, although I think both names are very pretty.
Have you considered the combo Julia Natalie?
EDIT: I just saw on one of your replies that you have a daughter named Liliana ("Lily"). Julia fits much better as a sister, imo.
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www.behindthename.com/pnl/69381www.behindthename.com/pnl/69381/109399www.behindthename.com/pnl/69381/91835http://greens-end.myminicity.comThis message was edited 1/10/2017, 7:57 AM