Meet the Other Phone. Protection built in.

Meet the Other Phone.
Protection built in.

Buy now

Please or to access all these features

AIBU?

Share your dilemmas and get honest opinions from other Mumsnetters.

Is this a normal adult sibling relationship?

117 replies

treasurechest92 · 02/01/2026 08:45

I have siblings and we are close but not to this extent. There's a long list of things that have been bothering me, and I don't know if I'm overthinking. Friends have given mixed opinions. A bit of background and a few examples....

Dh has one sibling, they are both late thirties. I like his sister, she is a nice woman.

When I first met dh, he told me he would never move in with me as I live too far away from his sister (20 min drive).
On a weekend away once his sister was sent to hospital with appendicitis and he was planning to leave our weekend away to go to the hospital, despite her having her parents and husband with her.

His mum regularly told me that 'sisters child' is dh's soulmate.

During an argument about something entirely unrelated, he randomly told me he would rather spend time with 'sisters child' than anyone else as they are easy company (aged 7).

He once told me his ideal woman is 'homely, girl next door vibes, just like sisters name' which is the complete opposite of me, I am a heavily tattooed and not conventionally good looking woman.

On two seperate occasions where I've invited sister and kids to join in activities with us and our kids, she's been unable to attend so asked to rearrange time or day, I've been unable to due to work, so instead of sticking to original plans with me, he's rearranged and done the activities with her and I've been left out despite it being my original plan, and despite me asking him not to as I really wanted to see the kids doing it.

A conversation where sister was showing me a scar on her stomach and how much she hated it, to try and make her feel better I said my stomach is covered in stretchmarks, dh pipes up with 'scars are cool as fuck, stretchmarks are ugly'.

Once we were staying in a log cabin in the middle of nowhere, and sat outside at night and a man was watching us from across the trees and it made me really uncomfortable, I asked dh to go and say something and he refused. At a later date when discussing it, he said 'of course if sister was there I would have gone and had a word with the bloke as she would have been scared'.

The next two have both happened this week, which is why I'm writing this now.

On Christmas day night, kids were in bed and we were getting intimate on the sofa, initiated by him, both partially undressed and clearly wantong to have sex, I asked if he'd like to move to the bedroom and he said 'no, I'm going to phone sisters name'.

His sister showed up to an event wearing something I loved, I told her I love it and that I had actually been considering buying it but hadn't (as dh had said it was tacky, I didnt tell her this part). After the party, dh was gushing about how great she looked and I reminded him he had said it was tacky when I wanted to buy it and he replied 'tacky on you but sisters name can pull everything off'.

I have tried talking to him about the last two but he said theres nothing to talk about and put his headphones in.

I hate myself for thinking badly of their relationship but there are loads more examples than what I've written here. Twice this week I've seen her come up to him, lean against him and rest her head on his shoulder and it honestly made me feel a bit sick.

OP posts:
Jackiepumpkinhead · 02/01/2026 08:50

Yeah, this is really odd behaviour! Excluding the sister weirdness, your husband is horrible.

grinchmcgrinchface · 02/01/2026 08:51

Sorry but sounds like he wants to shag his sister, this isn’t normal at all. Very creepy!

treasurechest92 · 02/01/2026 08:52

I forgot to add when we were discussing baby names, he would say 'no because sisters name would hate it'

It's constant.

OP posts:
Harrriet · 02/01/2026 08:52

Why on earth are you putting up with this. You are worth far more. I don't think it's a healthy relationship between siblings, what does the sisters husband say/reaction.
When I was just married, my husband always put his family before me. It made me feel worthless.

grinchmcgrinchface · 02/01/2026 08:53

treasurechest92 · 02/01/2026 08:52

I forgot to add when we were discussing baby names, he would say 'no because sisters name would hate it'

It's constant.

Why are you even with him? What does sisters hisband make of their weird incest relationship

ObladeeObladi · 02/01/2026 08:54

Yeah…..I have three siblings and none of that is normal. It honestly sounds like he has a romantic connection to her. It may be that nothing has ever happened but the vibes are off.

But putting the weirdness of their relationship to one side (as I doubt you’ll ever know for sure quite what it is), imagine for a moment that it was just a female friend he was talking about. He thinks this other woman is more attractive than you, more stylish, a better life partner. Prefers this other woman’s kid to his own kids. Prioritises spending time with this other woman over time with you.

None of this is ok. I honestly think it’s a deal breaker.

Newsenmum · 02/01/2026 08:54

Are they biologically related?

ThisWeekIAhBeenMostlyEatinTrifle · 02/01/2026 08:55

Leaving the sister aside entirely, why are you with someone who is such a dick to you, and clearly doesn’t like you very much? It doesn’t matter if this is his sister or a stranger or a colleague, it’s his treatment of you which means you should leave him.

JulietSierra · 02/01/2026 08:56

Weird. I have three brothers and none of what you’ve written is normal sibling behaviour.

NotrialNodeal · 02/01/2026 08:57

This reads like he's in love with her. 😳

SweetBaklava · 02/01/2026 09:02

This is very very weird. I’m baffled why you are with this guy, it all sounds very unhinged.

Likeaburstcouch · 02/01/2026 09:02

Definitely dodgy and I'm concerned for his sister's child as well!

Newsenmum · 02/01/2026 09:03

Likeaburstcouch · 02/01/2026 09:02

Definitely dodgy and I'm concerned for his sister's child as well!

Me too. In plain sight. Sick.

danesch · 02/01/2026 09:05

ThisWeekIAhBeenMostlyEatinTrifle · 02/01/2026 08:55

Leaving the sister aside entirely, why are you with someone who is such a dick to you, and clearly doesn’t like you very much? It doesn’t matter if this is his sister or a stranger or a colleague, it’s his treatment of you which means you should leave him.

This is spot on I think. The sister stuff (while weird) is a red herring. He's not kind to you and doesn't seem to like or care about you.
I've been with my DH for almost 30 years, we were friends for a long time before we got together. At some point, and I cant remember if we were dating or friends at that stage, he said something about how his sister was the only girl who never annoyed him. He has a close, but perfectly normal, relationship with his sister, as do I (and she definitely annoys him sometimes!), but I still remember the comment because it struck me as so odd at the time. The sister-stuff you are describing is on such a different level to that I'm not really sure why I've mentioned it. But as others have said, the relationship with his sister doesn't sound like the real problem here.
I wish you well.

SugarCoatSandwich · 02/01/2026 09:07

It's not right but it's hard to tell if it's because, as you seem to imply, he is more into his sister than you, or whether its just that he is really nasty to you (he is) and you're seeing it because he uses his sister as another way to knock you down.

lemonraspberry · 02/01/2026 09:12

Two problems here. 1) The DH-sister relationship is (at best) stretching the boundaries of normal. I would love to know more about what the sister says about her DB - is this a reciprocal relationship status?
2) your DH is treating you appallingly, regardless of the sister situation. It is almost a mirror showing you how your marriage is quite toxic. He is not behaving as your partner or even friend.

and the 7 year old as his soulmate is just weird.

LilyBunch25 · 02/01/2026 09:17

So he basically wants to be married to his sister. The one that topped it for me was him wanting to phone her when you were almost having sex. Sorry. Weird does not even cover it.

Justlostmybagel · 02/01/2026 09:18

How have you married and stayed with a man, who is clearly wanking over his sister? 🤢

treasurechest92 · 02/01/2026 09:39

Yes they are biologocally related.
Sisters husband is pretty chilled out, they have been together since being early teens and he has never questioned anything that I know of.

OP posts:
glendabrownlow · 02/01/2026 09:45

I had a partner for many years at a different time in my life. He was similar over his entire family. I got fed up with being an 'also ran' and he was so surprised when I left him, but it was utterly relentless. No decision about us could be made until he had run it past his family and no opinion could be formed until he asked his whole family what they thought. Nope. Yours is even creepier than this, OP. Understand that he will not change and the sister will always come first.

thepariscrimefiles · 02/01/2026 09:51

Your husband is a fucking weirdo! If his obsessive admiration was directed at an unrelated woman, you would be convinced that they were in a sexual relationship. The fact that it's his sister makes it even worse, not better. It's creepy as fuck and it would absolutely repulse me.

grinchmcgrinchface · 02/01/2026 09:54

treasurechest92 · 02/01/2026 09:39

Yes they are biologocally related.
Sisters husband is pretty chilled out, they have been together since being early teens and he has never questioned anything that I know of.

You need to call your husband out on this weird obsession with his sister. Its not normal at all. He genuinely sounds like he wants to shag her. Ick.

EmeraldShamrock000 · 02/01/2026 10:03

Very weird behaviour, he is obsessed with his sister, his gentle, beautiful sister.
I dated a bloke in my early 20's who thought his sister was beautiful in a very weird way. ATT, I scolded myself for thinking he is interested in her but it was obvious that he fell in love with her romantically when they were growing up.

Daleksatemyshed · 02/01/2026 10:07

Have you talked to his DSis about this Op, just in a general way? I'd want to know if she's the same about him or if it's just him whose a bit obsessive . Quite honestly, any man who'd stop mid foreplay to call his DSis has a problem, get turned on then think of her, not on

Greentomatoes24 · 02/01/2026 10:16

Might be a reach, but I'd wonder about possible SSA when they were younger with the way he/they are carrying on.