Having been born in a developing countries and went to US for university and work sometime there, I can say that US minimum salary and the other related perks are already significantly way better of most of emerging countries.
Also, there will always be some worse off country to say "look it could be worse, see how lucky you are?" I think that is such a disingenuous and irrelevant point.
This might sound harsh, but I do think it's better of for her to hand her children over to foster care or something. Having to support 3 kids with such salary is just too much for her. What I was proposing was "how to prevent future Vanessa"