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Q: My daughters are 15 and 16, and my older daughter is bullying her sister about her breast size. My elder daughter’s breasts swelled up a lot when she was going through puberty, but my younger daughter was not as lucky. My younger daughter’s breasts are small compared with those of my elder daughter, who uses this as a way to pick on her sister. It goes beyond simple teasing and into obvious bullying territory. She is constantly mocking and belittling her sister. How can I get my daughters to sit down and talk about why they’re fighting all the time?

A: I chose this question for two reasons.

First, bullying among siblings is not uncommon. You don’t have to look far to find grown siblings with harrowing tales from their childhoods. Some of this bullying was not noticed by the adults in the family, or worse, some was applauded by the adults. These children, who are now adults, carry deep wounds.

The second reason I chose this question is because our culture has a deep misunderstanding of bullying and the roots of the behavior. Like other well-intentioned helping professionals, I used to think that bullying was a behavioral problem. I believed that bullies needed to learn a lesson and face the consequences of their behavior so that it would not be repeated. I remember having bullies face their victims to see the pain they had caused and apologize. There is no telling how much more pain I caused by doing this, but I was operating under the false — yet commonly accepted — idea that bullies could be bullied into remorse. I cannot go back and undo my mistakes, but I can share insights that will help you understand your daughters and allow you all to move forward.

First things first (this is the most important point): The way your elder daughter treats her sister is emblematic of her relationship with the rest of the world, especially adults. Pause to take that in. Your elder daughter bullying her sister doesn’t really have anything to do with her sister; instead, she has a deep wound, hurt or pain that is reversing her alpha instincts.

One of the instincts that plays an important role in all humans, but especially families, is the alpha instinct (for more information about this theory, see Gordon Neufeld’s work on attachment). If you are thinking of wolf packs, you are on track. Everyone is born with this instinct, which makes us want to take care of people, fill leadership vacuums, and do good for others in a powerful and loving way. If you’ve had a strong and loving teacher, a tender grandparent or relative with strong boundaries, or a remarkable and warmhearted nurse, then you know the impact and strength of the alpha instinct. These people step forward and know what you need. They can be affectionate without being weak. People have this instinct in differing levels.

If her alpha instinct were in working order, your elder daughter would want to protect and care for her sister. Does this mean that they wouldn’t fight? Of course not. Sibling fighting, disagreements and general nastiness are normal. Storms brew between siblings for a variety of reasons — where they are developmentally, hormonal changes, friendship and school challenges. These fights rumble in, make tremendous noise and then quiet down. During the lulls, children mostly get along.

So, yes, siblings fight, but I think your elder daughter suffered quietly and immensely when her breasts bloomed early. Most teens are consumed with being just like their friends. Early, large breasts are a difference that cannot be hidden, and they often attract the attention of the opposite sex in awkward and embarrassing ways. Other girls loathe and envy you for being curvy, while boys (and many men) stare and catcall. That leaves a young woman feeling exposed and betrayed by her body.

It may sound like psychological babble, but I think your elder daughter is taking out her pain and envy on her sister. Rather than protecting and caring for her sister, her instincts have reversed, and she is instead “mocking and belittling.”

Your elder daughter needs compassion, stat. Because the bullying is becoming chronic, please seek the help of a good counselor. She needs a safe and supportive environment to express her anger and pain, so a therapist who specializes in helping young women with body issues would be best. And for it to be effective, it’s important that your daughter like and trust this therapist.

Your younger daughter is also wounded. She can’t control her body any more than your elder daughter could. Call a family meeting with the girls and acknowledge that there has been a lot of pain, but tell them that you won’t tolerate any more mocking, name-calling, etc. Say that when you see it, you are going to stop it.

But — and this is important — don’t shame your elder daughter when you catch her being unkind. Break up the dynamic. Separate the girls. But don’t layer punishment and consequences on the elder daughter. Remember, the source of her behavior is pain. Any added pain will only fortify her defenses. We need her to soften, not harden, her emotions. Protect both girls.

I would also recommend doing what you can to keep them separated. Because the pain is acute and emotional work needs to be done, your elder daughter cannot be trusted to be kind, and your younger daughter cannot defend herself. Keeping them in each other’s orbits is a bad idea. This will be inconvenient, but it’s necessary.

And as long as you are separating them, I am going to ask you to connect to your elder daughter. Choose anything that you both like and do it together. Begin slowly, and carefully ask her about her interior world. I don’t know to what extent she will shut you out (I am guessing that you have been rightfully defending your younger daughter and that your elder girl feels pretty defensive), so please, be gentle. Connect with her in the easiest and most authentic way and save the lectures. Like any teen, she won’t respond to lecturing, anyway.

Lastly, be wary of the traditional books on bullying. They often won’t steer you in a direction that will ultimately help your elder daughter. She is hurting and needs strong boundaries, strong love and heaps of compassion. Good luck.

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