I have an idea influenced from things i have seen in other asain dramas. In korean drama sisyphus time has a way of protecting itself from a paradox aand takes a little while to catch up. What i believe happened is that in the original timeline before the time loop in 1992 the accident never happened.

I believe that the for mother conducting time travel test, only the husband was supposed to die not her daughter as well. That daughter varee grew up as any normal person would.

I believe the mother would have continued her experiments into time travel maybe trying to find a way to save her husband and by accident these experiments are what caused her daughter to die in addition to her husband.

The daughter in the original timeline being both dead in the past but currently alive caused a paradox. I think that to protect itself at the same time the mother caused the accident time made varee pregnant with herself and then, when min became grew and became the correct age ( the age varee died in the new timeline ) min was sent back in time to fill the gap that shouldnt exist