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Original poster

Dating sister's ex

92 replies

LoveFridaynight · 07/05/2025 08:06

It finally happened. I have 2 DDs 18 and 16. 17 year old has been out with a few different boys in the last couple of years, which is fine. 16 year old has never had a boyfriend.
One of DDs ex boyfriend is on the same course as my youngest. They became very friendly and he's now asked her out. DD1 is fuming even though they were never serious.
I get it though. You don't date your sisters ex. I'm not being unreasonable to think that am I? I feel for my youngest DD. She's autistic and struggles socially so she's thrilled to be asked out but why him? He knows they are sisters so why ask her out anyway.
I feel I should tell youngest to turn him down. Am I being unreasonable to say you don't date your sisters ex?

OP posts:
Original poster
LoveFridaynight · 08/05/2025 07:46

I understand people saying they wouldn't allow her to date him but she's almost 17. I can say she's not allowed but then I'm worried she'd start seeing him behind my back and I really don't want that.

OP posts:
Original poster
LoveFridaynight · 08/05/2025 07:43

As I said ever since DD2 became friends with this boy I have always said do not get in his car and as far as I know she never has.
I'm trying not to get over involved. I spoke to DD1 yesterday about what she said. She wouldn't tell me what she meant except for the fact that his personality changes when you're his girlfriend. I'm now going out of my mind that he was abusive to DD1. She wouldn't confirm that (which confirms in my mind he was) but said she is going to have a proper talk to DD2.
I'm really hoping this puts her off as I can actually picture her putting up with crap from him just because he's her boyfriend.
I did have a long chat with her yesterday and reminded her that her sister is more important than any boy but I'm not convinced she took it in. So bloody hard when she's with him 4 days a week.

OP posts:
EmeraldShamrock000 · 08/05/2025 07:42

Longtoe · 08/05/2025 07:41

The driving part is the main issue in my eyes

Show quote history

I wouldn't allow DD date him due to his driving, not because he is an ex, the driving part, is a huge issue.

Longtoe · 08/05/2025 07:41

EmeraldShamrock000 · 08/05/2025 07:38

It is not unusual.

I have 3 sisters, two out of 4 dated a sisters ex as teenagers, my younger sister dated my ex while I'm still in crush mode.

I dated my older sisters ex, we were all teenagers.

It caused trouble, we got over it. It is hilarious now that we're in our 40's

The driving part is another issue.

Edited

The driving part is the main issue in my eyes

EmeraldShamrock000 · 08/05/2025 07:38

A friend of mine married her sisters long-term ex, everyone moves on. 😅

EmeraldShamrock000 · 08/05/2025 07:38

It is not unusual.

I have 3 sisters, two out of 4 dated a sisters ex as teenagers, my younger sister dated my ex while I'm still in crush mode.

I dated my older sisters ex, we were all teenagers.

It caused trouble, we got over it. It is hilarious now that we're in our 40's

The driving part is another issue.

Longtoe · 08/05/2025 07:21

He was driving with DD1 at a stupid speed and crashed his car. Luckily no-one was hurt but he was obviously

in comparison with THIS detail? I wouldn’t give a flying fig about fact a sister’s ex.

This would be my concern. This. And for that reason she would not be allowed in his car.

CowTown · 07/05/2025 15:36

TY78910 · 07/05/2025 14:32

this thread is fascinating. I’m a millennial and there was always a ‘girl code’ or ‘bro code’ where you don’t date your friends exes. No matter if it was a ‘fling’ or serious relationship. Just curious as to why siblings are different.

I’m Gen X and we had the same code…Chicks Before Dicks was what we called it.

TY78910 · 07/05/2025 14:32

this thread is fascinating. I’m a millennial and there was always a ‘girl code’ or ‘bro code’ where you don’t date your friends exes. No matter if it was a ‘fling’ or serious relationship. Just curious as to why siblings are different.

Foodfinger · 07/05/2025 14:31

This reply has been deleted

Message deleted by MNHQ. Here's a link to our Talk Guidelines.

CowTown · 07/05/2025 14:05

Katemax82 · 07/05/2025 12:24

I married my sisters ex..last time I posted that on here I got flamed

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Your sister and your husband have had sex? #awkward

MerlinsBeard1 · 07/05/2025 12:32

Your DD1 has had sex with this boy. He is a little creep to go after her younger sister. Your DD2 is autistic so may be a bit vulnerable to his advances and might not see how it is socially unacceptable.

I wouldn't have it, that is for sure.

Katemax82 · 07/05/2025 12:24

MayDayFlowers · 07/05/2025 08:08

My relative’s MIL married her sister’s ex! If they weren’t serious, I would keep out of it.

I married my sisters ex..last time I posted that on here I got flamed

Dingalingalong · 07/05/2025 12:03

It must be a difficult position to be in, for the 3 of you (I put myself so much in your shoes that I had put "us" 🤣), and I can't stop thinking about this boy stirring shit between the 3 of you and I find that really nasty, tbh. Just for that fact, he isn't a good choice for either of your DDs. You can ask DD2 how she would feel and what she would say if the roles were reversed. Also you can tell her that her sister is for life, a boyfriend isn't (she might not believe anyone is interested rn but that won't always be true). However, whatever logical, clear headed, convincing advice you can give, at the end of the day, they will make their own mistakes and learn from them. Your love and care for them shows and that's already enough ❤️

Original poster
LoveFridaynight · 07/05/2025 11:56

I don't know how much his driving has changed (if at all) and have already told DD2, when she was just friends with him to never get in the car with him.
DD2' keeps saving how much she likes this boy and I have tried explaining there are lots of other boys (that haven't dated her sister) but she says no-one else is interested which I find heartbreaking.
I'm going to have a chat with DD1 later and either find out why she no longer likes this boy or get her to tell DD2 which would probably be better. Whatever it is might be enough to put DD2 off anyway.
Thanks for the replies. I try to remind myself they are growing up but DD2 is vulnerable and I worry about her being taken advantage of.

OP posts:
SmoothRoads · 07/05/2025 10:50

I would encourage the younger daughter to listen to her sister about her experiences with this boy. I find the reckless driving very concerning.

Dingalingalong · 07/05/2025 10:36

NineteenSeventyNine · 07/05/2025 10:25

To those advising OP to stay out of it: her youngest DD is a child with additional vulnerabilities, and the boy in question could’ve killed her eldest DD by driving dangerously. The situation a bit more complex than a normal minor spat over a boy!

Also this! He sounds like a plonker and a liability.

Dingalingalong · 07/05/2025 10:35

LoveFridaynight · 07/05/2025 08:51

DD1 and him were together for maybe 3 months. I know they had sex at least once in that time but near the end of the relationship.
This lad seems nice enough, but does have a tendency to do stupid things. He was driving with DD1 at a stupid speed and crashed his car. Luckily no-one was hurt but he was obviously showing off/ trying to impress her. DD1 said to her sister (not me) you don't know what he's like. But I don't know if she's just saying that because she's annoyed.
They usually get on pretty well. They do bicker but nothing major.
Okay seems it's okay to date your sister's ex. I'll keep out of it. Although I am going to try and find out what the you don't know what he's like comment is about.
I just worry about DD2 so much. She's so easily led and always sees the best in everyone but I also know I have to let her grow up.

I don't think it's OK to date your sister's ex, ever, when your sister clearly says she isn't OK with it. If she was fine with it, no problem, but your DD1 clearly said she's uncomfortable with it, for whatever reason. There are enough fish in the sea to throw this one back. I know that if that had happened between me and my big sister, she would have never forgotten it and our relationship would have suffered - she's a very sensitive, insecure person and she wouldn't have trusted me the same way ever again. It's not worth creating such a crack in your daughters' relationship. I'd explain to your DD2 that she can feel flattered and happy to be asked out, but that once people have had a relationship, however short, it's part of them and it could cause mistrust between her and her sister, so not worth it.

NineteenSeventyNine · 07/05/2025 10:25

To those advising OP to stay out of it: her youngest DD is a child with additional vulnerabilities, and the boy in question could’ve killed her eldest DD by driving dangerously. The situation a bit more complex than a normal minor spat over a boy!

Nopersbro · 07/05/2025 10:24

You cannot tell your daughter not to go out with this guy. But of fucking course she shouldn't. Maybe it's best to have her older sister tell her why it's a bad idea to date this creep, and help her brainstorm how to prepare for a real first date with someone who likes her for her?

Maddy70 · 07/05/2025 10:21

Keep out of it. Let them sort this out. My niece married my other nieces ex.

JHound · 07/05/2025 10:13

Your youngest DD is in the wrong but you should stay out of it.

LilacPony · 07/05/2025 10:12

LoveFridaynight · 07/05/2025 08:51

DD1 and him were together for maybe 3 months. I know they had sex at least once in that time but near the end of the relationship.
This lad seems nice enough, but does have a tendency to do stupid things. He was driving with DD1 at a stupid speed and crashed his car. Luckily no-one was hurt but he was obviously showing off/ trying to impress her. DD1 said to her sister (not me) you don't know what he's like. But I don't know if she's just saying that because she's annoyed.
They usually get on pretty well. They do bicker but nothing major.
Okay seems it's okay to date your sister's ex. I'll keep out of it. Although I am going to try and find out what the you don't know what he's like comment is about.
I just worry about DD2 so much. She's so easily led and always sees the best in everyone but I also know I have to let her grow up.

I wouldn’t let any one near my family who had crashed their car with my daughter in it

IMustDoMoreExercise · 07/05/2025 10:08

LoveFridaynight · 07/05/2025 08:51

DD1 and him were together for maybe 3 months. I know they had sex at least once in that time but near the end of the relationship.
This lad seems nice enough, but does have a tendency to do stupid things. He was driving with DD1 at a stupid speed and crashed his car. Luckily no-one was hurt but he was obviously showing off/ trying to impress her. DD1 said to her sister (not me) you don't know what he's like. But I don't know if she's just saying that because she's annoyed.
They usually get on pretty well. They do bicker but nothing major.
Okay seems it's okay to date your sister's ex. I'll keep out of it. Although I am going to try and find out what the you don't know what he's like comment is about.
I just worry about DD2 so much. She's so easily led and always sees the best in everyone but I also know I have to let her grow up.

Well, if he was showing off and crashed, I wouldn't let your daughter in the car with him for a few years and I would try to put her off him altogether as he sounds like an irresponsible idiot.

TheKeeperOfTissues · 07/05/2025 10:05

As a young stupid teen I 'dated' my older sisters ex. I knew she'd be home & deliberately took him to the house to piss her off (it didn't 😂)
When it didn't get the reaction I was looking for I dropped him.

I like my sister now btw.

You are obviously looking out for your daughters. Keep doing that and they will be fine 🏵