Background as much as I know. All girls 10-11.
Yrs 1-3 M and little brother live with parents.
Yr 3 parents split, M and brother 100 with dad. Mum seems to be no longer around.
Yr 5 mum takes M back to home country for family funeral. Brother stays here (assume not his family; dad is actually M's step dad?)
Yr 6
September: mum moves back to village. Seems to have M and brother 50:50.
M tells DD her mum was violent when she got angry and would hit and throw things. M says also she wants to be violent when she gets angry and she can't stop it because it's who she is. Starts crying every break time DD wants to play with other friends. Ends up with DD no longer wanting to go to school because she wants to play with her friends and not constantly look after M, but doesn't want to be mean to M and leave her all by herself because if she doesn't stay with M, M is alone.
October: M outright lies to me about DD being invited to a Halloween party at her dad's. She had planned (and got permission from her mum) to go trick or treating alone with my DD.
Beginning Feb: divorce finalised.
Today: M tells DD that her mum had to pay her dad a £40 court ordered fine as she was 1 minute late home from contact with her mum. Also because of this her mum couldn't eat for half a week as they don't have a lot of money. Also that if mum ever gets a job she will have to pay dad £5000 a month. Also tells DD her dad didn't let her have breakfast this morning as she hadn't done her homework.
This afternoon:
DD says she was told L insulted her by saying "fuck you" about DD when L was talking to someone else. (This doesn't even make sense!)
I asked if DD had heard L say it - no, she was told (by M) that L had said it. Another boy, who has been known to bully L in the past, confirmed M had said it.
M encouraged DD to go and tell the teacher that L had insulted her, but when she saw L already talking to the teacher, ran away.
Phone call from L's mum asking if I knew what had gone on in school today. Apparently M threatened to stab L with a compass... walked up to her with the compass in her hand with the point out and raised her arm as if to stab her with it. She didn't actually stab her. When L asked what M was doing M said she was upset her mum had been fighting with her new boyfriend.
L told her mum she hasn't said anything about DD. DD and L have always got on - not best friends but no real issues, random play dates and often invited to birthday parties.
It seems to me it's a repetition of what happened at the beginning of the school year. Feed DD a sob story that I can't really check is true or not, then try to isolate her from her friends in her class. Either way, DD is feeling the weight of being confided in about such things. And it seems to me M might be in need of some help in processing her parent's divorce. I clearly can't ask either of the parents. Or any other parents. Should I speak to school?