Cath,
I am the eldest of eight children born in less than 9 years. I am almost 50.
When i was a child/teen I did act in a bullying way to to some of my sisters. Often it was teasing gone too far. Mostly it was a case of intolerance, boredom and abusing my power as the eldest.
Sometimes my sister annoyed me just by her presence. She was often sulky and sullen and humorless. I annoyed her just for entertainment and to get a laugh from other siblings. I didn't physically hurt her, but I verbally teased and niggled. Sometimes I just gave her hateful looks. Over time it wore her down. My parents didn't intervene as they thought 'kids will be kids'. Plus a lot was done out of their sight.
These days I am a lot more self aware and feel very badly for the way I behaved. I have apologised in a long letter many years ago, but my sister didn't accept it. She disappeared for 20 years from the family (the bullying is a small part of the story, but add in mental health issues, feeling 'different', a broken marriage, allegations of sexual abuse etc) and only returned on Friday!!
Anyway, what I am getting around to is...your sister may feel very guilty and confronted by you. If you need to discuss what was said, how about writing a letter - maybe hand deliver it or read it to her (writing the letter will help you chose the right words).
Start off by saying that you want to have a good relationship and thats why you need to tackle an issue that has been upsetting you. Try and show that you have some empathy (eg i know it must have been difficult to hear my accuations against your child and so you naturally defended her). Try to stay calm and walk away if she begins to abuse you, yell etc.
If she can't accept responsibility for her actions and give you the apology you seek, what kind of relationship would that be? Where would the trust and respect be? Show her where the line is that she has clearly over stepped.
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