When your baby is in the breast milk bath, it is completely ok for you to leave the baby and play with bath toys for about 10-15 minutes. This will help the baby’s skin to absorb all the nutrients from the milk.
Once done, there is no need to rinse the baby, all you need to do is simply pat them by using a dry towel and moisturize using baby safe lotion to help further lock the moisture and nutrients that the baby has observed.