8 Signs of a manipulative sister-in-law


In-laws are known to cause problems. It’s a universal phenomenon. When we come across universal human traits, we can be sure genetics has a vital role to play.

Like many other animals, humans obtain love, care, and support from genetically close relatives. The more your genetically close relative helps you, the more they’re helping their own genes.

Your genetically close relatives want to help you survive and reproduce, but they’re going to put themselves first most of the time. So, they’d want you to prioritize them over your spouse.

After all, your spouse isn’t genetically related to you and your family. This is the root of all the problems caused by in-laws. This genetic dissimilarity is mainly why many in-laws find it hard to get along with each other.

Your family may have problems accepting your spouse, and your spouse may have difficulties accepting your family. People like to blame either the spouse or the in-laws. But, in most cases, both contribute to the problems.

Of course, not all in-laws cause problems. Some get along very well with each other.

Things change with marriage

Siblings spend a lot of time with each other and share a special bond. This bond gets threatened when one or both of them get married. They now have to divert their time and attention to their own family units.

Siblings who cannot deal with this change will likely turn into manipulative brothers or sisters-in-law. If their jealousy and manipulation are left unchecked, they can cause significant problems and stress in your marriage.

Signs of a manipulative sister-in-law

In this section, we’ll look at the common signs of a manipulative sister-in-law. If your sister-in-law has problems with you, you might have already ‘sensed’ it more than once. You may have noticed that she treats you differently.

Going through these signs will provide you with further clarity:

1. Invading your privacy

A manipulative sister-in-law feels she has the right to interfere in your married life. She’s unable to separate her brother’s relationship with her and his relationship with you.

In her mind, there’s no boundary between her brother’s relationship with her and his relationship with you.

She thinks she can freely interfere in her brother’s married life with complete disregard to how it might make you or him feel. She uses her relationships with her brother as an excuse to invade his and your privacy.

She might:

  • go through your things
  • go through your husband’s things
  • ask you personal questions
  • ask your husband personal questions

2. Being passive-aggressive

People become passive-aggressive when they want to be aggressive, but something stops them from being directly confrontational. So, they become indirectly or passively aggressive.

Your manipulative sister-in-law would like to be aggressive toward you. But she knows you’re her brother’s wife. So, she has to restrain her aggression and behave more passive-aggressively.

So, instead of being overtly rude and nasty with you, she:

  • blames you
  • criticizes you
  • spreads rumors about you
  • gives you backhanded compliments
  • throws sarcastic remarks at you

3. Judging you negatively

Since your manipulative sister-in-law doesn’t like you, she finds excuses to justify her dislike of you. She’ll complain and judge you negatively, saying things like:

“There’s no food in the house.”
“You don’t know how to cook.”
“You don’t know how to parent.”

When you make a mistake, she’ll smile through her teeth and find it hard to hide her delight.

4. Draining your resources

At the root of all the problems caused by in-laws is selfishness. Basically, your sister-in-law doesn’t want her brother to drain the family’s resources into his own family unit.

Siblings compete for family resources since childhood.

When one sibling gets married, the family may over-invest in the marriage. This threatens the unmarried sibling.

Your manipulative sister-in-law may get jealous when your spouse invests in you. She’ll try to make sure you don’t get a piece of the pie when her family invests in her brother.

Worse, she might even drain your and your family’s resources to help her own family.

5. Controlling your marriage

The goal of all manipulation is control. Many couples can tolerate the invasion of their privacy to a degree. But what is particularly hard to tolerate is when your in-laws show authority over you and your husband.

When your sister-in-law makes decisions for you that you and your husband should’ve made, you know her manipulation has reached the next level.

6. Turning your spouse against you

Your sister-in-law, who doesn’t like you, wants her family to dislike you as well, especially her brother (your husband). She wants to mobilize an army against you because she knows you’re more likely to get crushed if everyone turns against you.

She’ll fill the ears of your husband with negative things about you. She’ll ask him to prioritize ‘the family’ over his family unit (you and the kids).

7. Treating you as an outsider

How in-laws treat you can be very similar to how minority communities get treated by the majority in any country.

If your in-laws don’t accept you, you’ll feel it. You’ll feel like you’re trapped among a bunch of strangers in some foreign land.

Your manipulative sister-in-law will treat you like an outsider by:

  • not inviting you to important family functions
  • keeping you out of key family events
  • keeping you out of family discussions

8. Accusing you manipulating your husband

While your sister-in-law manipulates your husband against you, she accuses you of manipulating your husband against her and her family.

“You’ve changed my brother. He was never like this.”

She may accuse you of ‘stealing’ her brother. Again, this is caused by her selfishness, insecurity, and either-or thinking:

“My brother can either be devoted to her or me, not both.”

Living in harmony

In this article, I assumed you’re the innocent one getting manipulated by your sister-in-law. If you are and have tried your best to get along with her, these signs that we just went through likely strengthened your convictions.

In many cases, however, both parties are at fault. If you can see how you might be contributing to these problems, you can significantly improve your relationship with your in-laws.

Your husband is probably torn between you and her sister. But he has a crucial role to play. He needs to balance his relationship with you and his sister. Sometimes, he may prioritize you and sometimes her sister, and that’s okay.

Put yourself in your husband’s shoes. You may also find yourself in situations where you prioritize your own family over your husband or vice versa.

Don’t catastrophize these events by saying something like:

“You always prioritize them over me.”

Does he?

This is a biased way of thinking.

Just because they prioritized their own family once doesn’t mean they don’t care about you at all. Get rid of this short-term thinking and look at the bigger picture.

You’ll know when things go out of hand. You’ll know when you’re being unfairly treated. It will be a pattern, not a one-off event.