Try putting baby in a swing, vibrating chair, or cradle, and pull it into the bathroom. Then shower away, and know that you CAN'T be the only mom that pops her head out of the shower to check on the baby mid-shampoo, mid-conditioner, and mid-shaving...right?!?
(If your bathroom, like mine, is too small to fit the baby, the doorway works just fine:-)
You might find that, even once your baby is older, you still use this trick. ;-)