I think wi/wo sounds like a good idea, if she is quiet whilst you are stood there but gets upset when you walk away then wi/wo may teach her that you will return and she is fine to go to sleep on her own.
The idea is that you lay them down and say night night to them (something like, time to go sleep now, mummy loves you very much etc.) and then leave the room. If she gets upset (properly upset, not just whingy) go back in and lay her down and then say exactly the same thing again and leave. Don't stay around for too long, Dominic sometimes will throw his teddys on the floor for me to pick up. If he does then I leave them on the floor, otherwise we'd be there all night picking up the teddy!
Be prepared for the long haul the first few times. It took an hour of walking in and out the first 2 times with Dom, then it was half an hour, now three weeks later I don't usually have to walk back in more than 2-3 times.
Let us know how you get on
Sal
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