Hi Sally i have the exact same problem, Liana bites Elisia. It always seems to be when she is getting tired or over excited.
I have tried so many things, i pull her away and explain in a stern voice it hurts Elisia and she must not do it.
She just laughs at me and i know she does not understand what she is doing. I even show Liana the marks she leaves but she just says "oh dear!" when she sees them.

I was told it is very common amongst twins and they do grow out of it.
Advice given to me was to try and keep an eye on Liana and distract her if i ever see a biting episode coming on.

What i found that does work is Liana has a book she carries everywhere, it is her comforter. I threaten to take it off her and have done on 2 occasions and it seems to make her stop for a while.

Sorry i have not been much help as i am still struggling with it myself, just thought it might help to know you are not alone.

Best Wishes
Love Carmela

 

Sally & Carmela,
I have the same problem with Anna biting Katie. She is usually really sweet to Katie (who steals her toys and generally rules the roost) but sometimes completely loses it and bites her in frustration. She did it twice last Saturday (hadn't done it for ages before then), once on each arm and Anna just laughed when I told her off, even though I was stern and held her by both arms etc. It has definitely got better though and they fight lots less than they did even a couple of months ago.
Sorry I have been no help, but just being stern and reinforcing that it's not kind etc., is my only solution and that doesn't work too well yet anyway!!! 
Jane
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