Okay so I'm making eggs in Pokemon black two since I'm trying to get all the Pokemon for my pc and I put my ditto and my nidoran (the girl one)in in the daycare. I got a egg from the old man and it hatched into a boy nidoran. How is this possible if both the nidoran in the daycare are both girls?
It's a random chance for each gender. The parent's gender's have nothing to do with it.
And BTW, it's still counted as a genderless Ditto, not a female Nidoran, so that wouldn't have anything to do with it even if that was how it works.