Ex partners new partner calling my son "mum"

[Mummaonherown]

My ex has a new GF, they met end of October and things have moved quickly, they are "in love" however when he sees me, he always "tries it on" with me and has stated he doesn't think his feelings for me will ever fade.

Anyway, we had an agreement that new partners would not be introduced until 6 month mark, my son is on the ADHD waiting list and still wants "mummy and daddy" to have days out with him.
My ex collected our son on Saturday and took him swimming, when he came back I asked if he had a good time and he said "yes I went swimming with daddy and mum"
I asked my ex if she was there, he said no however my son has stated on 3 separate occasions with my family members and my friend and her mother that "mum" was there and this morning my son has said he wants to go swimming with mum and daddy again.

I have corrected my son, and told her what her name was, but yet he keeps saying "no it's mum"
AIBU for not thinking this is right?
My ex will deny she was there

You need to tell your Dick X, that DS is saying Rachel was there & has decided or told, (by him or her ?) to call her Mum.
This is not happening, It is confusing for him & disrespectful to you.
He already has enough difficulty without this & your X needs to get on board with the program.

@AlexP24 firstly I’ve known this man since I was 22, so a long time - I don’t see him every now and then, I’m fortunate enough to have childcare - I will call him my partner as that’s the way it’s heading. I did say past June, that could be in September, October or November. I have no intentions of introducing before hand.
6 months is a good starting point - as a minimum! I’m not in the wrong here, I’m doing things the right way not introducing 2 men to my son in a space of year!

@RubyFlax I’m pretty certain, my ex does this “nervous laughter” when he lies and that’s what he done on Saturday when I asked him when he dropped he off.
My ex will lie about things he doesn’t need to lie about 2 weeks ago this “woman” didn’t exist he told me it fizzled out and they don’t speak anymore, this was when he was trying to get into my knickers.
He will lie to save his own skin, he’s thrown me under the bus quite a few times.
DS was very detailed this morning, said he went into the blue car and on the slide with “mum”

@AlexP24 yep that’s my thoughts as well.

Sorry but it seemed more likely to be a mispronounciation than a new woman telling he bf's son to call her mum. Atleast in my world but apparantly there are batshit crazy people out there..

So weird, can you just cut the toxic etc out & talk to the other woman? Address that it's weird, not good for your son

My DD called my friend Mam, bc her son did. She didn’t realise it was a different word for mummy. It could be a similar mistake. She was around 4 years old. She was adamant that was her name too.

@TiredMummma I wish I could, but I think a smear campaign against me would have already started. My X is very manipulative, he's been trying it on loads with me and sends me messages of what he would like to do with me, blah blah. He knows if I met her, I would probably tell her before another child is brought into this mess, so therefore he will do everything in his power to stop us meeting.
But I agree it's weird behaviour. He done his nervous lying laugh when our son said it in front of me on Saturday afternoon, I know he's lying

I can see why he's an ex. He sounds like a complete twat.

@SezFrankly I know what your saying, but I do think she was introduced as "mum" my son was with his dad, he wouldn't just say the word mum without someone saying it, someone must have said something and from my x's reaction I'm sure this happened

@Ellie56 and a cheat as well + he's not paying correctly for his son, he's fraudulently claiming benefits while working (not declaring income) now I know why he's doing it, he's spending most of his money on the new GF. I'm having a nightmare with him.

He sounds like a real piece of work 😩

does she have kids

Have you asked your son why he calls her mum?

Was it a typo or did you mean to put that your ex sometimes stays over when visiting your son? This would be far too confusing and pretty inappropriate given you both have partners and you say he’s constantly texting you about wanting to get in your knickers. If he wants to see your son, he can take him out or to his house. Your son won’t have a clue what’s happening if his father lives there some days but not others.

Maybe he couldn’t remember Rachel’s name and used ‘mum’ as a way of covering!?

What a knob he sounds. I’m sorry OP.

I think your problem is the piece of shit you had your son with.

He's goading you and you are biting. If the other lady treats your son well and he likes her let it be. Nothing can take away the fact that you are his mother. A rose by any other name smells as sweet. Even go as far as telling your lousy ex you think it's sweet . That'll people piss on his chips. Unless she's the OW.

that is hurtful op

Urgh the ex sounds like a pathological liar. He’s going to find it harder to lie as your son gets older and his speech develops. You’re doing all the right things, OP. I can see why you’re concerned.

If he is that insistent on 'she is mum' then it would seem that he's been pushed towards that but a child can choose that ie a dad s partner is mum as in 'mum and dad'.
We foster and obviously we are not mum and dad, the kids know we are not mum and dad, we have good relationships with mum and dad, however when they were younger they would call us mum and dad at times. This was accepted by SW as children were trying to 'fit in' in social situations so as not to stand out ie park, swimming etc.
My concern would be your sons insistence, that shes mum, with you that its adult led.

however when they were younger they would call us mum and dad at times. This was accepted by SW as children were trying to 'fit in' in social situations so as not to stand out ie park, swimming etc.

thank you for pointing out at least one scenario - and this is just one- where it is certainly kinder to the child to let them use language that they are comfortable with regardless of the feelings of adults.

This is not the same at all. I say that as someone who was not raised by her parents. Apples and oranges. You were their safe place. This woman is a stranger and it sounds like it’s driven by dad. It’s confusing and potentially harmful.

@yourmaw no she doesn’t.

@Namechanged4obviousreasons I think you read that wrong. My ex collects his son on a Saturday twice a month, sometimes my son stays at his PGM with his dad sometimes he doesn’t. My ex hasn’t stayed in my home for months now.