I get sad when babies separate from their mothers

It’s none of my business but I feel sad when I see a girl give birth young, and then continue on living life. She leaves the baby with her grandparents or parents, and she finds a new man to make new babies with. So she makes new babies, and has a husband now. But her first baby is all alone and with the grandparents :/ And then you see the mother or with her new kids in another state or something :/ like whaaaaat. I mean idk why I’m thinking about it so much, it’s probably because I see it often. It makes me sad thinking of what the first child is thinking. Why does that happen? (Again I know non of my business) but why bring that child into the world and give your other children the benefit of having a real family while you stray away from the first? 😕