THE PROBLEM: My older daughter (9) is constantly belittling the younger one (7). Believe it or not, they’re the best of friends. But the little one looks up to her big sister so much, she’s willing to put up with all the passive-aggressive snipes my older daughter sends her way. For example, she might say: “Too bad your hair looked so bad at Kelly’s party.” Or, “I was going to ask if you wanted to sleep in my room tonight, but I changed my mind.” I mean jeez, why did she have to even mention it? My younger one gets so dejected when her older sister does this, but still, they hang out with each other a lot, so I don’t often interfere. Now I’m wondering…should I?

MARY SAYS: One of the worst things that can happen in a situation like this is for mom to start ‘correcting’ the relationship, thereby inserting herself and turning the dynamic into a battle for approval (or disapproval) from mom. You have been wise NOT to do this. I’m sure it’s been difficult to hold your tongue when your older daughter mistreats her little sister, but you’ve exercised restraint.

You haven’t made yourself part of the problem, which makes it much easier for you to be part of the solution.

Each of your girls needs a conversation with you. Your older daughter is developing a behavior pattern that most likely manifests beyond her relationship with her little sister, and it’s up to you to address it. Let her know you’ve observed her unkindness—making snide remarks, belittling others, and making people feel bad about themselves. Go ahead and use examples of how she’s treating her sister—but use other examples as well. You may have been more tuned into what’s going on between your two girls, but if you can step back and be more objective, you’ll probably observe that your daughter behaves this way toward others as well.

Now for the little one. Without your guidance, she may grow up having difficulty with boundaries and an inability to recognize when someone is mistreating her. Sure, you’ve got examples to share with her right there at home, but ask her if she’s finding herself playing this role in other relationships as well.

Awareness is the key to addressing these behavior patterns in both of your daughters.  Children often have no idea they’re creating an unhealthy dynamic, which is what you’re there for. By helping them identify how they’re mistreating themselves or others, they can begin to pay attention and choose to respond differently. A more loving relationship between the two of them will simply be a byproduct of each of them deciding they want to present to the world in a healthier way.

ERIKA SAYS: I grew up with four siblings and many cousins, so I can say from experience this isn’t uncommon. We would all get along until we didn’t. A little sibling rivalry never hurt anyone, but if this occurs as often as you say it does, I think it’s time for you to step in. If there’s one thing I wish my parents had done differently, it’s that they would have intervened more than they did.

Perhaps sitting back was their way of “teaching” us how to problem-solve amongst ourselves. I’m not sure; I guess I should ask! The reason I wish they had stepped in is that we're all different, and some of us were more sensitive, like me. I didn’t know how to speak up for myself.

I was teased in elementary school and bullied in both middle and high school. This pattern even followed me into adulthood. No one taught me how to speak up for myself and create boundaries, and I feel like I often attracted people who mistreated me because it was what I was used to. If somebody put me down, they must like—or even love—me!

I’m sure your oldest is a lovely kid, but I fear that if she’s not redirected, her behavior will become a toxic trait she’ll carry into adulthood.

Here’s where you come in. Every time she’s unkind to her little sister, call her out on it. When she says things like: “I was going to ask you to sleep in my room tonight, but I changed my mind,” let her know that didn’t come off too nice. Point out that it wasn’t necessary to bring up, especially since she hadn’t been asked. Encourage her to consider her words. Was she trying to hurt her sister’s feelings or simply speaking without thinking?

In those moments, you can also teach your youngest not to let her sister treat her that way. Help her find the courage to say: “When you did this, I didn’t like how it made me feel.” Tell her it’s okay to love her big sis, but she mustn’t tolerate being mistreated. You want her to feel confident enough to voice how she feels and make purposeful decisions about what she will and will not accept.

If you have a question for Mary and Erika, we’d love to hear from you! [email protected]

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Erika Guerrero is a freelance hair and makeup artist, Erika K. Beauty, single-mama to one amazing boy, and author of She’s Not Shaken, a blog offering hope and encouragement to women in all walks of life.

Suzanne Johnson, mother of five children and grandmother of eight, is an illustrator, book cover designer, and author of the Realms of Edenocht series.