Grandmother often refers to herself as "Mom"

She needs gentle reminding that YOU are "Mom/mum" and she is Granny/Grandma orvwhatever.
Easily done, many of us find that Mum/Granny etc slips out. Not a big deal though

Can't quite get my head around this. My name tag is indelibly etched in the family circle and proudly so. Methinks I would be quickly queried (even corrected?) by the GC who are 4 and 2 respectively. Yes, I think it would undoubtedly have rankled with me had it happened but I'm sure I would have addressed it on the very first occasion.

You are not being unreasonable, nip it in the bud , or a gentle tease about loosing ones marbles & getting confused!

Or perhaps on a nicer tone ask her to choose a lovely pet name that is special to her & her GC

My mom is known as Nana by my children and I've never heard my mom refer to herself to my children as "mom/mommy"...so I wondered if it was a normal thing for someone to do on a regular basis...

Thanks. I will correct it the next time I hear it.

Tell her to stop it now. No excuses. Doesshe want to confuse the child or annoy you?

Look there's definitely a strained relationship but despite the past, I am and will always to include them in the kids lives, however, when we do see them, I have noticed she refers to herself as above and often. So I wonder if it's to annoy me or because she secretly wishes she was their mother lol...

why are so many mums on gransnet - is mumsnet not enough?

I do know that when she was in her earlier mothering years, she did send her kids to her mother a lot of the time and my husband often speaks of spending all weekend at his grans house and how he didn't enjoy it. As it was almost an every weekend story. So maybe she's missed out on being "mommy" to small children and now is trying to make up for it? I'm not sure what the reason ishe behind it but it's creepy.

Mumsnet doesn't offer sound advice. Gransnet seems to offer more constructive advice.

We don't swear enough for Mumsnet.

My mum did it a few times, I just said in front of my son, 'no I am his mum, you are my mum'.

Sounds like she's doing it to annoy you. How old are your children?

They are 8, 4 and 2.

I could understand saying it by mistake a few times here or there but this seems to be too often to be passed of as a slip up.

Thanks for the all the comments.

Don't overthink this.
Correct her gently or get the kids to call her "mum's mum" if you like.
Don't sweat the small stuff.

How old is your mum? My mum frequently gets the generations mixed up. Sometimes refers to herself as my DSs mum, sometimes refers to GGCs as her GCs. We just laugh it off. My DSs know who their mum is and my GCs just accept Nanna is a bit forgetful. Never quite sure who she thinks I am when she makes a mistake- her sister possibly I'd just gloss over it. If she's doing it deliberately to annoy you she'll stop it, if it's just a memory slip she'll carry on.

The GC very occasionally call me Mum when they are with me on their own - I make a joke of it and say : "I'm not Mummy!" In fact my DGD did it just now while I was typing it!

My sister is known as Mum to her grandchildren and their mum in mummy! I have always found it a bit bizarre- so perhaps there's history of this in the family. Is she/you American ( mom/mommy ) or when she talks is she just referring to herself as mom when talking about the kids parents?? It is odd but maybe the question needs asking gently? I cant think that she means harm!!

My GC used to call their dad, Granddad, by mistake, after they'd gone home from here.

Yes, agree that it should be nipped in the bud. You could say something along the lines of "The children are confused about what they should call you - can we think of a nice name instead of 'Mummy'?' Like others have mentioned, my GC often mistakenly call me 'Mummy' but instantly laugh and correct themselves. It looks like MIL is doing it deliberately rather than making a mistake...

Conversely my GS often calls me 'mummy' ..... I always correct him and say 'grandma' ....a bit of a standing joke now! Then again I often call him 'S' my son's name. I often hear my OH telling him to "ask Mummy" meaning me. I often think these things are a slip of the tongue. I understand your irritation and would just correct her nicely each time! Don't be upset. The relationship between some DILs and MILs can be awkward. You're the Mummy x

You'd think the 8 year old would have said something.

I'm sure all retired teachers here will remember being addressed as 'Mummy' by their pupils. Easy to laugh off.
It's a family joke that we confuse names - mum did, I do and DD does too. I once called out the dog's name when speaking
to my son!
I do think this is different. Has it been the same throughout the life of the 8yr-old?
Have you established a name for her?
What goes in birthday/Christmas cards?
If the name is there just make a clear point of using it often.

such as 'don't be silly Granny, you're not my Mummy'.

Even our 4 year old DGC would probably have giggled and said 'You're not my Mummy, my Mummy is my Mummy and you're my Granny'.

that was in response to Ana's post

and yes, mcem my DS got used to being called by the dog's name. It's when you have several children all claiming attention at once that you can get .
I got used to answering when I was called by my brother's name.