DS's name

[redtrees]

This is starting to bug me and I'm not sure of the best way to approach this, or if at all I should do anything.
Part of me wonders whether I should just suck it up but on the other hand it's difficult to let it go.
Basically my MIL always always always calls my ds by his 'cutsie' name. When he was a baby we used to use it sometimes too in an informal way but he's a big toddler now and it doesn't sound right, in fact i try and avoid it now as it is a very cutsie baby name iykwim. I've gone right off it tbh. In fact, I'm starting to bloody hate it.
MIL is quite forthright and outspoken and although most of my family call him by his proper name (and always have done), some other members of her family have also been using the cutsie name all the time due to the knock on effect. For example, in all cards, Birthday & Christmas presents, conversations, everything. They never use his proper name even though me and oh rarely if never use the cutsie name.

I'm actually starting to think she thinks that is is proper name! I really don't know why. Or, it could be that she has decided that's what his name is as it's really strange that she hasn't picked up on the cues from the rest of us who never call him that.
Anyway, sorry that this is so long but I do feel I need to say something...but how? Or should I let it go?

Is the cutesy name truly terrible?

If yes, say something, if no, leave it (he will grow out of it eventually).

When you say big toddler do you mean 3+? At that point they usually have opinions about what their names are.

Fwiw my big toddler is adamant that his name is although he will graciously answer to .

What does he say when you ask what his name is? It is his name now, not yours IYSWIM, so it for him to decide although some tactful steering is of course acceptable.

That would annoy me tbh. I don't like the shortened versions of my sons name, so we insist that his full name is used. But my dh's friend will always shorten his name and it winds me up. Even my mum does it and that bugs me as well. We politely tell them that we prefer his full name to be used.
Now my mil will do the opposite and use not only his full first name but his middle name as well, as though it's hyphenated (which it's not). That annoys me even more as there's no need. And the other thing that bugs me is when people insist on saying baby .......... Why can't they just use his name without putting baby in front?
Sorry I went off on a tangent there. But personally I'd say something. If you don't stop it it will only continue

What sort of name are we talking about? Is it that his name is Benjamin and you used to call him Benny and now don't like it and call him Benjamin, or is it that you used to call him Dinkums as a baby and MIL still uses it?

Sadly, though, you don't have an enormous amount of control over what people decide to call your kids.

If he is a big toddler, he is old enough to correct her himself. If not, wait until he is. Other wise you will send out a bit precious.

Thanks for your replies.
It's more of a benny/Benjamin scenario as mentioned above.
Ds refers to himself as his proper name.**
Hopefully he'll correct them himself, although I might start dropping heavy hints maybe emphasising his name more. Its just starting to really wind me up.

Correct mil in front of ds and ask him to tell mil what he likes to be called.
She's being very disrespectful to yours and ds's preference.

I would make a point of it and let everyone know that DS wants to be called x.

I recall my younger sibling once refusing to come downstairs until we stopped calling her by her 'baby name', we genuinely kept forgetting until she stamped her foot

My nephew - just started reception - told me off on my last visit. I use the endearment 'baba' a lot in my interactions with the toddlers and he's decided he is no longer a 'baby'.
I got a glowering look and a firm "I'm not a baba. I'm a big boy!"

Can you tell he's very proud to start 'proper school'!