Hi Jade
It sounds really intense situation. A whirlwind. I don't have that experience you describe, but I know that by focusing on your own self care and your other kids, and taking the focus off your daughter for as much as you can, can only help the situation.
Have you got a counsellor who can support you? What do you do to take care of you ?
By caring for yourself you will be modelling behaviours which may rub off on your daughter. If they don't, you still benefit and you deserve love and care so much.