Diplomacy tips needed please - irritating grandparent pet name

[IrritatingPetName]

Resisted posting this in AIBU (deep down I probably am) but something is really bothering me and I'd appreciate some advice from all you lovely minor family dilemma experts

My MIL and FIL use a ridiculous name for 'grandad' that sets my teeth on edge. They used it for their other, now teenaged, grandchildren, it always bothered me then, but hey - none of my business, right?

However, now its being used for their new little GD, who is just getting to the talking stage, but a probably few months off and I feel I really want to nip it in the bud before we get stuck with it forever.

How, oh how, do I approach this knotty problem without causing offence, turning it into a big deal?

We don't see them that often, as they don't live close by, but we have weekly phone-calls and will soon be going away on holiday with them. I have an okay relationship with them, but not bosom buddies, so it's not something I could slip in casually.

Oh and before you ask - DH is no help on this. He agrees with me, but doesn't feel strongly about this kind of thing. Men, hey?

My mum and dad are Nags and Grumps (their choice), and my ds is Peanut (initials KP). Fine, except for when ds tells his friends he is "going to nags and grumps house", as they have no idea what he means!

My Grandparents wanted me to call them Monkey and (can't remember the other odd one) many years ago and my parents said no as they didn't want to be like my other cousins who ran riot everywhere. I ask you who calls their grandmother 'Monkey'

Aaah, just let them have their own pet names. Why do they have to conform? Grandparents are always subversive anyway, that's their job, to teach kids that parents are not omniscient.

I don't have a leg to stand on as I call my DS the most ridiculously wide range of pet names which change all the time (but he always knows I mean him!). I try to call him his real name in public though.. hope I still won't be calling him Dolly Mouse when he's 16

My mother's family always called the grandfathers Papa, it is not uncommon in Scotland. My Dad always said that he would be a Papa rather than a Granddad, but then I went and married a German who is Papa to the children. Dad settled for Grandad after all.

Janzila
Your PILs are calling your DC we'ans (wee anes = wee ones) and it is a term of endearment and nothing to do with Wayne. I really like it when our relatives from the West Coast of Scotland call them that.

oops, Janzilla sorry, forgot a L

About the OI, I think that is a regional thing too, I seem to remember my mum's cousin shouting that. I don't think I would say anything tbh, your we'an (sorry, couldn't resist) will get used to it.