I answered it, but really I'm the same as Andrea. Can't remember well enough to find the mode or anything, but it's almost always more than once. I put three just as a guess. Anyway, my mom does the same "more than once" thing. My brother, however, only sneezes once as far as I've heard, and I've never heard my dad sneeze.

(And that was way more info on my family's sneezing habits than anyone would want. Sorry.)