Can Moshiach ben Dovid be a girl?

Someone I know and like is joining the blog just as soon as she figures out what to call herself. Meantime, here is her second post

My kids like to ask me about difficult topics. God, for one. Death, for another. Salvation, the afterlife, the Chosen Nation, reward and punishment, and so forth. And of course, mashiach. "When is he going to come?" "When he comes are we going to move to the Beis ha-Mikdash?" "My teacher said all the shuls are going to fly to Yerushalayim. How are they going to fly if they aren't airplanes?" Etc. So I provide straight answers to the best of my ability, watering it down for age purposes, generally trying not to confuse them by blatantly undermining their teachers unless it's absolutely necessary.

So over Shabbos my five year-old daughter asked me, out of nowhere, if mashiach can be a girl. I have to say that threw me for a loop. I mean, CAN mashiach be female? To the extent that there are texts on this topic, I confess to not being very familiar with them. Is there any actual reason to say that no, it's impossible for mashiach to be a woman? I imagine that there is such a reason, but I don't know it, and I never say anything unequivocal if I don't have the background to explain it fully.

So, not knowing what to say, I went with the old parental stand-by that usually works wonders for us in cases like this, and I said to my daughter, "That's a very good question. What do you think?" And she said "I think mashiach could be anyone. Because otherwise, it wouldn't be fair."

Works for me.

Update: The author adds: "I realize the texts say "him", but if it were in fact possible for it to be a him OR a her, the texts would STILL say "him", since that's the "generic."