How often should I bathe my baby?

It sounds like your sister in law is a little obsessive. I give my daughter a bath once a day (at night). We do the whole bath, bottle, bed routine and it works very well for us. I also use the Johnson's bedtime wash and lotion and she sleeps well. Im not sure if the wash/lotion have anything to do with it but, it smells wonderful :) I don't think you're lazy at all. It's completely normal to only give your child a bath everyone other day, especially while they're so little and don't play in the dirt all day long! :) Aubree had some issues with spitting up, so that's why I started giving her a bath every night. Now that we're in that routine, Im going to keep it that way. Her skin is not dried out at all. But other babies skin may not tolerate being washed every day :)