My old boy used to get a bath whenever he rolled in fox-poo or something equally disgusting. So some months not at all, some months twice.
My young boy, OTOH, seems to get pretty dirty and smelly fast without rolling in anything obvious
Possibly all the puppy saliva he gets covered in when playing?!? Mud? Kids sticky hands?!?
Whatever it is, he had his first bath 2 weeks ago and I'm having to sit on my hands not to stick him in the tub again...but I'm guessing bathing too often is not good for their skin? Then again, I have no idea - just guessing.
How often is ok, please?