Do you give your baby a bottle of extra water in addition to the formula? I give my 4mth old formula only. I did try to give her an extra bottle with cool water in the afternoons after being advised to do so by friends who do this (mainly to keep their babies BM's regular), but she doesn't like it and won't have anymore than 10 mls. Is extra water necessary if your baby isn't constiptated, does anyone know?