On s upon a time a 13 year old was considered an adult, a young adult but still capable of making rational decisions (like babysitting children and self care). It's funny that you're saying she's screwed either way because she wouldn't be if people like you were rational. It's not ideal to have to leave for work, but it's not like she left toddlers alone, she hired professional adult supervision in addition to the supervision of the teens. Some of the adults in your life were latchkey children who walked themselves to school and handled their own affairs. You should speak to them and ask them about it. Some of those adults babysat family and friends children as young adults themselves far before they could drive.
Attitudes like yours destroy communities and the next generations independence. Fuck learned helplessness.