My normally very well behaved 2 1/2 yr old loves her 4mth baby sis and generally is very good with her but, three times now she has bitten her and i don't know how to disipline her. She is always immediately sorry and tearful after having done it but at 3 times i feel something has to be done. I would normally use a naughty step but i'm not sure if its appropriate.
Please help