A postpartum mother is concerned that her newborn has not had a stool since birth. The newborn is 18 hours old. What is the nurse's best response?
a) "I will call your pediatrician immediately."
b) "Passage of the first stool within 48 hours is normal."
c) "Your newborn might not have a stool until the third day."
d) "Your newborn must be dehydrated."