Just that really!
My DD is nearly seven months old now, and has a really sour, vinegary smelling bum, although I think it's more the vaginal region.
She gets bathed in just water every night, baby soap twice a week, though I dont use soap on her girl bits (the very thought makes me itch!) Nappy every two to three hours if she hasn't pooed. I wipe her thoroughly each time.
Why is she smelly? I can smell it through her clothes?