If the little 2yo girl has a history of hurting other children why was she unsupervised int he nursery? I know nornally the odd thing will go unnoticed in nursery - well, anywhere tbh. But a little one with this kind of behavioural history - no, she should be being watched ALL the time.
I don't like the DM's take on it though. They are really making out this 2yo child to be evil and as for those referring to her as Chucky - horrible, This child has issues and needs them addressing, not having grown adults calling her names and labelling her. TBH the labelling will make matters far worse - a child who is told they are bad all the time will be just that!
But I have real sympathy for the 3yo little girl who has such horrible inuries. The poor child. And yes, if it was my child I would be so so cross, and hurt and upset, and very protetive of my child.
And of course the police can't do anything - how can they deal with a 2yo for goodness sake!!!
But I do think the 2yo's parents should be being spoken too, the child being referred and for now - the child not being in that setting.