Mentioning Willow Smith's fluency in a fake alien language is hilariously irrelevant. That's like saying "My mother in law has big hairy feet, can I be in the next Hobbit movie?" Or like saying "A guy I know has read the Harry Potter books three times, can I be in Fantastic Beasts 2?" Oh Jaden Smith, don't ever change. It would be kind of neat though if Willow Smith was actually fluent in Na'vi, and with her and Jaden cut from the same cloth, it is certainly possible. I can't imagine the fluency rate is very high. Avatar remains the highest-grossing movie of all time, but it hasn't exactly had a major pop culture presence in the years since. Plus, who would she even speak to? Her brother speaks an abstract and rare form of English, but apparently not Na'vi, so the practicality and applicability of such a skill is somewhat limited. This also raises the question of how many people speak a fictional language worldwide. I figure Na'vi must be near the bottom of total speakers, certainly below Klingon and Elvish, but possibly ahead of Dothraki.