chewing metals

my child is  6 years one of twin .easy to cry doesn't have self confidene .always try to behave like any one. from 2 years begane frequantly rubing her lips with her shirt chewing eraser and pencils.and finally i find circle metal she is chewing in her mouth please help what can i do?

[paperclip46]

I  think you must find out why she has no confidence.  My son at that age ate paper.  I found out later that he had a perceptual delay. We took him to an Occupational therapist who sorted out the problem. Today he is a very confident young man. The occupational therapist will take her through a number of tests to determine what is happening.
Best thing I did for my son.

[Sandman2]

   Very good point by paperclip.  You might also want to find a substitute for what your daughter is chewing on.  She sounds anxious and needs something to soothe her.  A small ball that she can squeeze would be really good.  Gum is much better than metal.  But essentially, the twin competition maybe getting to her.  Find a way to help with that.