Wet nurse, milkmaids.
There have always been women that have the capability of lactating without being pregnant.
I am not fully educated on the process but I know it involves suckling.
I have known of pregnant women or women that have given birth that do not lactate as well.
Ever hear the phrase her milk did not come in?.
Google is a mofo. The crap I just saw regarding this is intense. Hormone pills/shots, teas, vitamins... Too much for me buddy. Everone has their "thing", thats just a bit much for me.