YAY I love the name [name_f]Sienna[/name_f]. Of your optinos, I would vote [name_f]Matea[/name_f]!
[name_f][/name_f]I love the suggestion of [name_f]Lucia[/name_f].
[name_f][/name_f][name_f]My[/name_f] other ideas would be:
[name_f][/name_f][name_f]Emelia[/name_f] [name_f]Maria[/name_f]
[name_f][/name_f][name_f]Alessia[/name_f] [name_f]Josephine[/name_f]
[name_f][/name_f][name_f]Milena[/name_f] [name_f]Carla[/name_f] [name_f]Maria[/name_f]
[name_f][/name_f][name_f]Chiara[/name_f] [name_f]Josephine[/name_f]
[name_f][/name_f][name_f]Adriana[/name_f] [name_f]Maria[/name_f]
[name_f][/name_f][name_f]Violeta[/name_f] [name_f]Carla[/name_f]
I also think [name_f]Liana[/name_f], [name_f]Arianna[/name_f], [name_f]Livia[/name_f], and [name_f]Audrina[/name_f] could match.