Parents in law mispronounce daughter’s name

A different version of the same problem and probably a wild overreaction given you’re talking about grandparents/grandchild: I didn’t take DH’s name when we got married 2 decades ago. ALL of his extended family call/write/address me by his surname. I just thought it was them being so small minded / backwards that they couldn’t wrap their heads around a woman choosing not to lose her identifier just because she married, so privately pigeon-holed them as such and stopped doing any “wife work” as it pertained to them (why would I expend any energy on people who don’t even know my name, let alone see me as merely an extension of my DH).

I subsequently learned MIL had told them all to address me as such because she was so affronted that I didn’t take her son’s (her HUSBAND’S!) name. I now do no “wife work” as it pertains to her.

I’ve had decades of this posturing. In your shoes, with my history, I’d be telling her to call DD Sarah because she’s seemingly incapable of pronouncing DD’s actual name and maybe that would be easier for her. Life is too short for this BS. (A less fed-up, menopausal response would be to ignore it because very soon your DD will be calling her out on it and she will have to explain herself to a 5yo child).

I love the name it's beautiful.

A simple but direct 'I'm aware that you are not keen on the name add-eh-lin so I suggest that you call your granddaughter her correct name of add-eh-line. ' I had a similar issue where my mother in law would go on about a particular point which upset me, (she was being very unpleasant) and I was constantly polite about it, in the end I said 'you're upsetting me and if you mention it again I will have to assume you're doing it on purpose and trying to upset me' . Her behaviour improved no end after that as she realised I wasn't going to be a pushover any more and she needed me I didn't need her. She probably was trying to upset me, but she realised I wasn't going to play the game any more. Things are better now.
I think sometimes people need to know they have to make an effort and it does matter.

Very pretty name. Your DH needs to have a word and explain how upsetting it is for all of you.

This is so unbelievably petty and passive aggressive on their part. What has your partner said to them/how are those interactions dealt with?

I suppose they're aggrieved because they didn't get to dominate the naming of their granddaughter above the mutual wishes of her parents.

Watch out for other creeping control tactics. My ex MIL would try things like publicly humiliating me by very loudly and forcefully taking over basic tasks and "showing me to do it yet again", deliberately mispronouncing my mum's name (not a tricky name to pronounce...)
Even went so far as saying she just wouldn't say her name at all if it was such a fuss... great🙄

I love this. Please try this and report back. Adeline is a great name btw!

Can your spouse/partner have a private word with them about the name?

Enough of the polite corrections. Their son needs to ask them directly 'why do you repeatedly pronounce our daughter's name incorrectly?'

Urgh. They sounds dreadful. Just stop including them in stuff or inviting them over if they can’t even respect your name choice. They’ll soon get the message. It’s a beautiful name by the way, and your pronunciation is the most ”common” one in my view and

I’d just say that. If you can’t pronounce her name correctly just call her Addie please as you will confuse her and it’s upsetting us and DS.
Has DH not had a word?

This isn’t the correct answer and you probably shouldn’t do it, but I’d be tempted to keep mispronouncing this names and see how they like it.