Re: bathing
the pH in baby shampoo might be a little harsh but it <span style="text-decoration:underline"><em>may</em></span> be better then normal shampoo. Bunny Bath is a good choice for shampoo - it's pH balanced and shouldn't irritate the skin.
2steps is correct. While some people on this board recommend bathing every month, the majority of cavy owners don't think it is necessary. Bathing too often can cause dryness and skin irritation. If you pig does need to be bathed often you may what to increase it's cage size or increase the amount of times you change the bedding.