Lol. Guess what, everyone's house has a gender neutral washroom in it. Just go in and lock the door. Not rocket science.
That said, in my house the washroom door is usually unlocked right now. I can be taking care of business and I have a troop of kids and wife march right through. The only defense is a strong aroma (for my wife). My kids don't care and will happily sit on a stool and watch dad poop. o_O;;