And it provides some immunity from viruses that the mother has been exposed to and built up a natural immunity to.
I'm not sure at which age that immunity "wears off" for lack of a better phrase. But newborns and very young infants have some immunity to viruses because of it.
The infant immune system is stronger than most people think and beats adults at fighting off new pathogens.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4707740/
Because the child is not full of toxins ….. YET
And it provides some immunity from viruses that the mother has been exposed to and built up a natural immunity to.
I'm not sure at which age that immunity "wears off" for lack of a better phrase. But newborns and very young infants have some immunity to viruses because of it.