I'm sorry for your loss
If the remaining one was attacked on Saturday and she has not been eating/drinking or you haven't been getting any fluids into her as of today (Wednesday), I would say that her chances are not good. If she is still lethargic after all this time, then it may be kinder to end her suffering.

If the remaining one was attacked on Saturday and she has not been eating/drinking or you haven't been getting any fluids into her as of today (Wednesday), I would say that her chances are not good. If she is still lethargic after all this time, then it may be kinder to end her suffering.