I like [name_f]Belle[/name_f]! I don’t think it’s common, but [name_f]Bella[/name_f] is and there may be some confusion with that. Whenever I was in school if there was a girl named [name_f]Sophie[/name_f] teachers often called her [name_f]Sophia[/name_f] in the beginning, and if there was a girl named [name_f]Isabella[/name_f] they would often call her [name_f]Isabelle[/name_f]. I think it can get confusing when there are similar names with E and A endings which is something to keep in mind. However, [name_f]Belle[/name_f] is beautiful and if your niece loves the name I wouldn’t let that deter you. I like [name_f]Fia[/name_f], but I prefer Phina (common nickname for [name_f]Seraphina[/name_f] which is very similar to [name_f]Sophia[/name_f])! This may be more distinctive for [name_f]Sophia[/name_f] and shares the phi and a sounds. Phina can also be spelled [name_f]Fina[/name_f]. [name_f]Hope[/name_f] this helps!