The nutrient that is not digested but keeps the digestive system healthy is C. Vitamins :)
The placenta develops within the first couple of weeks of pregnancy. The placenta is the lifeline of the fetal body and soon after the placenta is developed and in place, it begins starting to absorb nutrients for the developing fetus. This all occurs in the first trimester.
First just be understanding about it and second do a diet for them and with them
Answer:
Mouth.
Esophagus.
Stomach.
The small intestine.
Colon (large intestine)
Rectum.
( hope this helped goodluck! )