The real challenge is that the tools available to is, as a society, to punish perceived injustice are very few. We have fines, prison, and social stigma. You won’t get far with fines for a person already on social assistance. Social stigma is a non-starter in our climate; she’s a single mother trying so hard for her kids! This either leaves prison (as bad of an idea as that is) or admitting that we have not criminalized bad parenting and some people will absolutely RUIN their kids’ lives.
Just giving you context because it’s easy to roll your eyes at someone (“that dummy wants to send her to prison lol”) when I believe there is a deeper explanation.
In some ways, we do have a punishment system for parents with truant children, but it’s very hard to thread a line that’s actually good for the children. You want to scare the parents with punishment if they don’t have any intrinsic (or social) interest in educating their children, but actually jailing parents won’t help most kids one bit.
(Unfortunately this idea wouldn't work, since many of the slapped parents would doubtlessly slap their kids in retaliation.)