AITA for Allowing My Sister to Borrow MY Car Without My Wife’s Permission?

A Redditor shared his story of allowing his sister to borrow his car without consulting his wife, leading to a heated argument. The sister, who drove from out of town, experienced car trouble upon arrival and needed a reliable vehicle while starting a new job.The Redditor, who works from home and uses the car minimally, believed it was his decision since he makes the payments.

However, his wife raised concerns about her EV’s charge, their son’s comfort without AC, and the fairness of helping his family versus hers. After the argument escalated, she left with their son to stay with her mom. Read the full story below to decide if the Redditor was in the wrong.

‘ AITA for Allowing My Sister to Borrow MY Car Without My Wife’s Permission?’

**AITA for Allowing My Sister to Borrow My Car Without My Wife’s Permission?**

I (32M) recently allowed my younger sister (30F) to borrow my car without consulting my wife (32F), and it’s caused a significant issue. My sister and her 2-year-old daughter came to visit us and our parents for a few days before she starts a new job.

She drove from Phoenix to Albuquerque, about a 6-hour drive, but as she arrived, her car started making a grinding noise, and her AC compressor went out. Her car, a 2012 Jetta with 150k miles, is otherwise in good condition, and she’s always taken great care of it.

My sister asked if she could borrow my car for a few weeks until she got established at her new job. I drive a 2023 Kia Forte with only 3k miles. Since I work from home and only use the car to drop off and pick up my son from daycare—a total of about 10 miles a day—I didn’t see an issue.

I make the payments, and I’m the only one who drives it, so I figured it was my decision to make. My sister even joked about taking over the payments if she liked it, and I didn’t mind.

However, I didn’t discuss this with my wife before agreeing, and she’s furious. She just got a brand-new EV a few days ago, which she makes the payments on. Here are her concerns:

1. **What if her car runs out of charge and she needs to go somewhere?** My response was that she should keep it charged, just as I would keep my car fueled.

2. **She thinks I’m giving away something I worked hard for.** I pointed out that it’s my car, and I have the right to decide what to do with it. I didn’t question her choice to upgrade her car, even though it increased her payments.

3. **She worries about our son needing air conditioning.** I countered that we only drive short distances, and I can roll the windows down.

4. **She believes my sister should get a new car instead of borrowing mine.** My sister recently survived brain cancer, which destroyed her credit due to medical bills. I even had to cosign her apartment lease two years ago, but she’s always paid her bills on time, so I trust she would handle car payments responsibly.

Two years ago, I lent my old car to my wife’s brother when his was in the shop, and she didn’t complain. But now, when my family needs help, it’s a problem. My siblings and I had a rough childhood, and we’ve always looked out for each other. I’ve always helped my in-laws without hesitation, but when my family needs something, it’s a different story.

After a few hours of arguing, my wife tried to get me to change my mind, saying, “we” need a nice car, and that my sister isn’t insured to drive it. I told her to get insurance before she leaves, which wasn’t the answer my wife wanted to hear.

The argument escalated, and my wife eventually packed some bags and took our son to her mom’s place, saying she’d return the next day for the rest of her things. So, AITA for deciding to let my sister borrow my car without consulting my wife?

Here’s the comments of Reddit users:

carmabound −  NTA – Hopefully her mom has a newish car with air-conditioning, so your wife can take your son to school without issues.
It sounds like this is only the tip of the iceberg and resentment has been building over time, or perhaps she needs a different perspective to see things more clearly – but letting your sister use your car is up to you, and you’re not TA for allowing it.

Lisbei −  INFO: how were you planning to take your son to daycare and pick him up?

SDstartingOut −  ESH. But does it really matter what a bunch of strangers on reddit say? I’m single, never married. And even to me – this just seems like common sense of something that you would talk with your spouse about. At the same time, if this was an isolated incident (I doubt it), she’s over blowing this.

One thing you completely left out here: Does she ever use your car? I don’t care that you both pay for your vehicles separately. Does she ever use your car? I’m assuming yes (as she references using your car if hers runs out of electricity).. However, big cavaet to all this.

The argument escalated, and my wife eventually packed some bags and took our son to her mom’s place, saying she’d return the next day for the rest of her things.

You have bigger problems. It is extremely unlikely this is the only incident causing this. That’s pretty extreme. I have to assume there is a lot more to this. Frankly your concern should *not* be getting a verdict on something like this – when this is clearly just the tip of the ice berg.

My sister even joked about taking over the payments if she liked it, and I didn’t mind. I mean, last I checked, buying a car is normally two pieces. The down payment, and the monthly payments. Again this seems like you are making a pretty major life decision (potentially giving away 3-6k in equity to your sister), without consulting your life partner, who you have a child with.

ncsu-throwaway −  YTA, but not for being a good brother. This seems less about you lending your car to your sister and more about the fact that you are making a big decision without discussing with your wife, who is supposed to be your life partner.

Your sister half joking that if she likes it, she will just take over the payments, and you being okay with it is also an interesting factor. It makes it sound as though there is no plan to fix her car.

Why not help her fix the AC instead and allow her to make payments to pay you back or talk to your wife about consigning with your sister.

Does your wife know you cosigned for an apartment with your sister? Did you have a conversation with your wife beforehand? Did you discuss the risks of being financially responsible should your sister no longer be able to afford rent or the possible impact on your credit?

EV cars are great for local commutes and some shorter distance trips, but what if you have to drive long distances? The school may only be 10 minutes, but what if there is an emergency? What do you do when it’s humid and hot outside with a small child inside?

Do you keep your finances completely separate? Did your wife discuss getting a new car before she bought it? How old is your car? What was your down payment? What happens if your sister gets in an accident?

I get wanting to help your sister. Your sister has been through a lot and is a survivor, but she has medical bills, apartment costs, etc. Can she afford to take over your payments? Idk, but something feels off. I feel like we aren’t getting the full story from your end.

AmberLeanne89 −  More info: how is your child getting taken care of in regards to transportation? Is he supposed to be driven in the broken down car while your sister takes yours (which is what it sounds like), will you be sharing the vehicle with your sister, or will you use your wife’s car?

Your child’s safety should come first, and driving a car that isn’t functioning properly could be dangerous.. *Edited to change niece to sister

Low_Breakfast_5372 −  I mean… you’re married, so are the cars not communal property? How hard would it have been to just briefly discuss it beforehand?

started making a grinding noise, and her AC compressor went out. Her car, a 2012 Jetta with 150k miles, is otherwise in good condition,
This doesn’t just sound like an issue with the air conditioning. This vehicle may have a serious issue. It may not be safe for you to drive, especially with your son in the car.

What if her car runs out of charge and she needs to go somewhere? My response was that she should keep it charged, just as I would keep my car fueled.

She kinda has a point, and your glib response was not helpful. EVs don’t go nearly as far on a full charge as gas-powered cars go on a full tank. And filling up is quicker than charging up. Two years ago, I lent my old car to my wife’s brother when his was in the shop, and she didn’t complain.

You don’t clearly state here, though… did you discuss this with her beforehand? Was the vehicle nearly brand new, as your current one is? And even if the answers to these questions are ‘No’ and ‘Yes’ respectively, the difference in your wife’s comfort level is still understandable.

It seems fair to assume that she probably knows her brother a lot better than she knows your sister. My sister isn’t insured to drive it. I told her to get insurance before she leaves

The way you wrote this is a bit ambiguous, so to clarify… your sister will be insured to drive your vehicle before she takes it home with her? The argument escalated, and my wife eventually packed some bags and took our son to her mom’s place, saying she’d return the next day for the rest of her things.

Whooaa! That… seems like a huge leap. So much so that I can’t help wondering if you’ve left out something significant. If not, this does seem like a HUGE overreaction from your wife. I particularly don’t understand why she gets to decide that she can take your son without discussing it with you.

I understand your feelings on this matter… and some of your wife’s arguments were b**lshit… but I nonetheless feel that you may have been in the wrong with regard to the car (or at least with regard to not discussing it with her first). But I’m very curious how it got from that to what seems to be separation.

ugotthewronggoddess −  If it is so safe that the baby can ride around in it and it’s a cheap and easy fix, then why isn’t his sister driving her own car?!? If it’s good enough for the toddler, then it’s good enough for the grown ass adult women! Fix the 2 dollar fan belt that someone on here keeps spouting about fixing her car in one day. The problem is solved she has her own car back in 1 day.

Otherwise, YTA because anything like that should be discussed. You lent her brother your old car, so I assume she asked you, and you discussed it, right?! Like adult married people do. Did you have a toddler back then? Things change when you have kids. Priorities change.

Maximum-Swan-1009 −  *Since I work from home and only use the car to drop off and pick up my son from daycare—a total of about 10 miles a day—I didn’t see an issue.*

You don’t mention how your son will get to and from daycare, which to me would be the main issue. Does your wife now have to do this? If so, this could be making her life rather difficult.

SlinkyMalinky20 −  This isn’t about the car. I’m guessing there is a simmering resentment about how much you do for your sister and/or your sister taking advantage and/or your being generous for your sister/family to the detriment of your own.

houseonpost −  YTA: If you can use her car to drive your child to day care every day, surely she can drive her own car to her own work. Depending on where you live 10 miles could be a one hour commute.

By the end of the day your child could be sitting in a very hot car for 20 minutes to a half hour. Why would you put your sister above your own toddler? Your child is also your wife’s child so your decision has a huge impact on her.

You say you lent your old car to your BIL. Did you and your wife discuss that first? It’s also bizarre that you are on the first steps towards a divorce and you are talking about a car.