My son in law can only call me Granny

I think it's quite a common problem (if you see it as a problem!). Some in-laws find it difficult or awkward to use first names with their partner's parents.

I don't think my former son in law ever addressed me directly by name either - it was always 'your Mum' or 'ask Nana'.

Didn't bother me one bit.

My SIL does the same. Annoys the heck out of me, but that's him.He will also say things like 'Does your mum want a cup of tea/gin and tonic'(he already knows the answer to that one.)

In other respects he's a good bloke, and he and DD have a very stable relationship, and he is very tolerant of his MIL almost living on his doorstep. Sometimes I think it's a form of shyness, but like you he's had 10 years to overcome that. We could have worse problems with our children's partners so guess we have to ignore it.

My dgc all call me Ma as do all the DSIL. That's fine by me so long as they actually address me. DDIL calls me by my name and that 's fine by me. My Japanese dil called me Mrs Lester but she was strange!

And I certainly wouldn't want to be called 'Mum' by one of my children's partners. I find that very odd...

All our sons/daughter inlaws call us by our first names when speaking to us directly but of course do say 'say goodbye to Grandma and Grandad 'etc if speaking to the children.
So I don't think you are being unreasonable at all.

My DILs call me by my first name, which is fine by me, I don't want to be called anything else.

I think I days gone by deference was shown by calling older women Mrs .......... and not using first names until invited to do so.

I avoided calling my MIL anything. ( although I did have some names privately

My parents called their respective
in-laws Mum and Dad.
I didn't feel that I could do this with my PIL especially as I had lost my own mother.
However I also couldn't bring myself to call them by first name either
so I was left with husbands name followed by mum or dad ( which felt really awkward)until DC came along & then they came Gran & Grandad

I am happy my DD partner calls me by my first name.
My DiL doesn't use my name.
She will just say 'your mum' to my DS & more recently grandma as they now have a baby.

I don't mind what they call me as long as they call me.

On the other hand, "Granny" is better than "the old bat"

I found it uncomfortable at first when DS's partner called me Mum, but she seemed at ease with it. Her own mother lives a long way away and doesn't see her very often, so I accepted it as a compliment.

Have you ever established with him what you would like to be called? Perhaps it wasn't made clear from the beginning what you would prefer.

He must have met you before the DGC arrived on the scene - what did he call you then?

My DSIL and DDIL both call me Jal except when talking to the DGC

I am called Pat by both my daughters-in-law but didn't call my in-laws anything right up to when they died. I think they would have liked me to call them Mum and Dad. They certainly looked on me as a daughter. But I had a Mum and Dad. When I first met them I was only 16 and this was over 50 years ago. I was quite shy and wouldn't have dreamed of calling them anything other than Mr.......This seemed too formal. So time went on and they never invited me to call them Renee and Edwin so I didn't. I feel a little sad about it now.

Both my DH and myself were exactly the same as you pensionpat and did not call our in laws anything which was quite rude. I am very happy for anyone to call me by my first name.DiL and SiL do and even DS1

I never called my PiL anything. I hardly knew them so didn't feel I could ask their preference.
H has always called my mum, mum but called dad by his first name.
Before she met ex SiL D's boyfriend called me mother as "he was very fond of me but he already had a mum" I liked that.
Ex SiL did use my first name occassionaly but called H by his first name with ease. Odd that they both have done that.
D's new SO calls H and I by our first names all the time, we have known him since they were both about 10 so anything else would be wierd.

Have been called the old darling for twenty five years and also Annie because two of them worked for our firm , third son in law uses my Christian name

I have two daughters and three son in laws !

My DH was like that with my parents. He referred to them as grandma and grandad as long as they lived. He was asked, many times, to call them mam and dad, but he couldn't.
I am very lucky that my SiL calls me by my name, but he had been my Dad's boyfriend since she was 17.

If you cant beat him join him and answer him back through the grandchildren

I am Mum to my daughter, my first name to my son-in-law, and Big Granny to the kids. Makes for a lot of writing on the family Christmas card:-)

My SIL were very disrespectful in a hilarious way 😂

Just thinking about this and remembered that I don`t recall calling my MIL anything other than Gran , certainly never called her by her first name , she would not have liked that . My DILS call me Fay or Nana if the kids are there . Could you outright ask him to call you by your first name ? Maybe he needs permission .

Grammy6, is it only that he doesn't use your name or does he never speak to you at all?
Do you speak directly to him?

How did he relate to you before the DGC were around?

My DDiL has always called me by my name. Which I am more than happy with not the name, I hate that, I mean I am happy with the fact that she uses it

I never once heard my mum or dad refer to their in laws by any name . They were always ask granda, grandma whatever and when they were talking to each other it was always "your mum, your dad"

I think people get so used to giving the kids a running commentary and tasking them with little jobs that it becomes a habit.......at least you are included.

My dad used to call mum's mum, 'the old gyp' not when she could hear him mind...............

Our future SIL calls us Mummy & Daddy when speaking to us and by our first names when speaking about us to others. DD2s partner calls us by our first names. Future SIL always ends text messages to DH with MH (man hugs) rather than an X.

I found it very difficult ti call my FiL and MiL anything at first - mr &Mrs perkins seemed too formal, first names were just a nono then. ( his sisters H did call them by first names later and they did NOT like it! In the end i managed mum and dad whic is what DH called them as i called my parents mother snd father which terminology DH adopted. It became much easier when they became grandparents. However all my childrens partners call us by our first names and we are happy with that. Though they all tend to use grandma and grandad these days! But they do address us directly hich i think is the real problem in the OP.