She has the resources to (as one path) freeze eggs and have a surrogate when she gets out. Same kids, same existence only now they have a mother present for the first 10 years of their lives and they don't have to live wondering if their original purpose was a desperate attempt to keep their mother out of prison.
Or there's adoption of any number of real non-hypothetical already born children that will be around when she gets out at 50.
I once saw a Facebook group with the cutesy name "life is a stockholm syndrome and I want my money back". That's spot on.
Happiness is preferable to suffering.
Suffering is a natural part of life. So is happiness.
Suffering is inevitable. Happiness is not.
For some people the happiness outweights the suffering.
It's not a given and you can't really know in advance, but I'm pretty damn sure that having a narcissistic psychopath for a mother tips the scale towards suffering.
Sometimes the happiness outweighs the suffering by such a large margin that you can't even imagine that for others it's the other way around. Maybe you become one of those people who put other people in literal cages "for their own good" - you can get involuntarily hospitalized for expressing doubts in the value of your own life, you know. Even if you're right. Especially if you can prove it.
So that biases the answer you'll get, on top of the natural bias towards self-preservation and reproduction. It still doesn't make it anywhere near truthful.
Ever look up the origins of the word "proletariat"? It literally means "breeders". It's the people who own nothing but their own lives, have no capital other than their time and body. We're selling our lives to the highest bidder out here, man. We're cattle.
Would you teach your kid to be aware of that predicament? No, you would teach them to avoid the subject entirely. For their own good, you see.
Many people are forced to be alive, and just rationalize around that to make the process of staying alive comparatively easier. You can probably imagine what reasoning around such traumatic cognitive dissonance for the sake of sheer self-preservation does to your overall cognitive abilities, and by extension to your ability to make the world a better place so people honestly want to stay in it.
If you (in the future) ask these children I'm pretty darn sure that they would disagree that they would have been better off not existing.
But I guess that doesn't count because.. they're biased in favor of their own existence?
I'm only 30% trying to be sarcastic, and mostly trying to see if this kind of argument makes any kind of sense.