You know this thing where you start paying back if you earn more than £15k. What happens if the student person never earns any money?

I only ask because my fella's ex went to uni for 4 years, racked up lots of debt (lots of which WE are now paying off ) and rather than use her degree, she has turned into a baby making machine. (5 kids ).

So what happens to her debts? I doubt she will ever work - well not a fully time job anyway.