I know a pair of twins called Josh and Olivia and think they sound right together. If you're going for a more different name, I really like Liliana but only if you don't have a long last name. 4 sylables in the 1st name and a long last name might get a bit much! Lilly is such a lovely shortening. It's one of my favorite girls names but my DH's grandmother had that name and was a royal pain in the ar$e so that one has been vetoed by my hubby!