Ah, polygamy. You suffer from the disease of being male, don't you? At least Hermione's prominent and Luna's the other wife. Now, if there are even more wives, then you're really a moRon.
Author's response
Guilty as charge!
Didn't want to get into that whole multiple Mrs. Potter explanation but I do believe after everything was said and done there would be a large difference in the male/female ratio.