She was on to something. I've had more love and kindness shown to me from complete strangers than my entire family combined, who live to spite me. I keep telling my mom that people are generally good, it's what's got us living in the modern age, it's just that capitalism keeps the good people from sticking together.
My first guess was gonna be "The Origin of the Family, Private Property and the State" by Engels.
But the manifesto is basically a summary of a bunch of other communist lit, so I'm probably half right.