You’re right - also goat’s milk is a substitute I think some mothers use.
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My father as an infant could not digest cow’s milk. His mother got a goat, and pasteurized that milk for him. He thrived on it.
We did exactly that for my second youngest, born in 1997.
Raw goats milk at our place. Our healthy goats. Did not need to pasteurize. The only supplement we used was folic acid, can’t remember why. I was raised on the evaporated milk. Still prefer it for coffee or tea.