Lilliana

The name Lilliana is a girl's name meaning "lily, a flower". While Lillian is the English version of this elaborated flower name and Liliana is the authentic Spanish or Portuguese spelling that's pronounced the same, Lilliana is a hybrid spelling that doesn't exactly have its own cultural origin but that can be considered perfectly proper nonetheless. However you configure it, it's a lovely name and if it looks more appealing to you with three L's versus two, go for it.