7 year old biting herself

[workshy]

my 7 year old has started sucking/biting the tops of her arm and causing bruises

I've asked her why and she says she doesn't know but she isn't doing it in front of me so she knows it's wrong -she seems to be doing it in bed

she is a happy soul so can anyone shed any light on why she might be doing it and how I can stop her?

My dd sucks , chews and basically puts anything in her mouth and doesn't have a clue she is doing it! Has this just started happening? Is anything else going on that might be making her anxious? It could be just s habit - but worth trying to dig a bit deeper

she has been doing it on and off for about 6 weeks

I split up with her dad 18 months ago but he has had regular contact since and nothing has changed in regards to their routines so I'm at a loss really

It may sound silly, but does she have any loose teeth? My son does this when he has wobbly teeth, a bit like teething !

How about offering an alternative - I am often at my wits end with my dd and her habits. I now give her something to fiddle with to occupy her hands so she won't be stuff in her mouth. Is she doing it at certain times - when she is really tired?

I don't actually know when she does it -I've only actually seen her do it once and that was when she was sitting at the table waiting for her tea!

I notice the marks when she is in the bath usually

no wobbly teeth -I checked lol