To not want SIL to call my DDs these names?

[MrsMushroom]

Dork, wally, cork-head, twit and similar?

She's Australian and they do like her...she often says things like "Sit properly or your food will end up on the floor you wally."

it irritates me for some reason but I acknowledge that I can be uptight about language and I don't want them saying these things to people...they're 8 and 4.

Ongoing to call my children cork-heads when they get home. I love that one!!

Sorry, are you IN Australia? Are you likely to see a lot of SIL? if it bothers you, be direct, ask her not to.

Don't mean to pry, is it just this that's bothering you or is this the tip of an iceberg?

You know what you said earlier about being prepared to accept if you were BU...?

It sounds like it's just her way, but I would try and tactfully bring her up on it, partly because I don't allow name-calling from my children so it would be confusing for them if a grown up is allowed do it to them.
Also, your dc are going to start copying her! I know my kids would get in trouble at school for calling people any names meaning stupid.

Does it bother your kids? If not relax and let it go. Let her have a relationship with your kids without interference if it is not hurting them. I agree with PP, unclench.

Nip the saying it to someone else in the bud before it happens.

YANBU. I wouldn't like it, and I wouldn't want my dch repeating it - what if they started calling their Grandma a wally, or whatever?

It's a bit like Glasgow. I'd never use it, but "ya wee c*nt" can well be seen as a term of affection here!!

Different strokes!

I wouldn't worry.

Other Granny calls newborn DGD 'brat', for the crime of being asleep during her visit. Now that's grim.

Mine are doughnuts (silly) or monsters (naughty)

DS1 is called a bag of rats by my DSis

Minions generally do as they are told though don't they?

Mine would suck as minions.

I don't think yabu at all. I don't my children calling others twit and wouldn't want anyone calling them twit either. Just tell her