Would you want to meet your child’s potential in-laws?

I’d reserve judgement on the circumstances set out by OP. Completely understand wanting to meet potential DiL’s family and background.

so much so that I would offer to arrange my own holiday in their part of the world, and offer to visit them / probably better to invite them to lunch at your hotel.

if they still were unable to make time or did not immediately counter invitation you for lunch in their own home, I would be wondering why.

and thinking about what it might mean.

I don't care how little annual leave you have or how packed your schedule is, refusing to sacrifice half an hour for coffee in your hotel when invited is weird and rude. They're probably concerned you want some kind of involvement with the wedding planning.

I'd leave them to it and consider myself relieved of any obligation to be anything more than coldly civil towards them.

He’s 25 and, depending on when her birthday is, she could be still 23.

I think their refusal to meet up - even for a quick coffee is really weird. And very unusual for most of the americans I know (I live here). Is it possible they aren't that enthusiastic about the relationship and don't want to encourage it?

He’s 26 and she’s 23? In your initial post, you say that she’s 18 months younger…how does that work?

Given they were on holiday, they may have had a busy schedule.
I couldn't think of anything worse to do, than on holiday, meet up with people I have never met before.

I think it’s rude. As you’re only down the road and you offered to pop into the hotel, they could squeeze in 1 hour for coffee. Might have to assume there is something else going on-they’re unwell/on brink of divorce/embarrassed by their haircuts or something

Is there a reason none of them have met each other?

One of my sisters in-laws have met my parents briefly a few times over the years,

My other sister goes on holidays with her in-laws, my dad's been on holiday with her FIL and her husband, I've spent Christmas, holidays, days out with her parent in laws

My mum has only met that sisters in-laws a few times.... she claims not to like them but their really nice people, I think she's just jealous of how close they are to my sister 😅

They probably have their holiday planned to the last five minutes. I wouldn’t worry about this too much. Yet.

I also don't understand the focus on age - I think 26 is a great age to be engaged / married. I never got the whole - be with your life partner but just randomly wait years and years and years to be married. Never made sense to me.

My parents have met my husbands mum and partner 3 times in 30ish years including our wedding. They have only met his Dad at our wedding. I dont think they've met his Dad's partner as she left quite early. No aminosity anywhere. I think his mum would posdibly have liked to get to know my parents but they live miles away and my family arent the most outgoing and my family is tiny.

In contrast is my best friend... Jane married John. John has a brother called Chris. Chris married Clare. Jane, the brothers and Claire's extended families all got together regularly. We're talking like 50/60 people. Chris died. Clair and her family were still part of the collective. Clare remarried Clive. Now Clive's family has also been absorbed into it even though he has nothing to do with any of it and I just think that's lovely.

That is truly , exceptionally weird. I'm sorry but it is.

I don’t think it’s weird at all. They’re on their holidays and want to enjoy that. You are strangers and likely to remain only passing acquaintances in the future. They’ll meet you next year. It’s not a big deal.

I don't get why you are desperate to meet them tbh. If I was them I would prioritise the rest of my holiday too. You can meet them next year.

Not odd of you, but the fact is a lot of Americans only get two weeks' annual leave. Nothing you can do really.

Phew - I was starting to think that my friends, family, DH and I were all child brides from a strange cult and backward part of the world

I would like to meet them, sure, but it wouldn’t upset me that they’re too busy.

I tend see marriage as the going of two families. That being said, I have family in the USA - annual leave is precious.

You talk as though they're just turned 18! It's totally normal to be getting married at 26. I'm only a few years older and went to plenty weddings in my mid twenties including my own.

Also - in the USA they are lucky to get two weeks of annual leave. They really will be wanting to jam pack the trip. Don't be offended - they are happy to host you next year.

Perhaps they thought it would be a bit awkward all meeting up (without your son and daughter in law there too) as a first meeting would ordinarily be with your children to introduce you? I can imagine it would be very awkward without those two to be the common thread!

My parents have never met my husbands parents and we have been together 23 years. They (husbands parents) couldn't come to our very small covid wedding, and had never met them prior to that. They've met his sister and her (now ex) partner and that's it. They're very different people and while they'd all be very polite to each other, I very much doubt they'd get on.

My parents have met my brothers in laws at their weddings and a few family parties.

Indeed.

OP said, "He has been very serious about her for a good four years; to my knowledge he has had no other partners."

I can't see any post from the OP that says or implies that the young lady has not had previous relationships. Perhaps she has not - but that is not what OP said.

They're hardly young to get married ! What a strange attitude.

Going on holiday & being expected to waste some of that precious time is unreasonable. US have far less AL than UK - used to be a mere 2 weeks.

And you have an offer from them for next year.

People in the US get very very little annual leave. I think it's entirely reasonable that they want to use their expensive UK holiday for relaxation. They're happy to meet you, just not at this time.

Also, yes, I think it's a bit odd that you're desperate to meet them. You live on different continents, so are unlikely to have a close relationship as you might have done had you both lived closer together.

What impact do you imagine it will have on your son's life, if you love them vs if you hate them? Or them you?
I imagine he's made his decision on marriage, so whether you like them or not, is, unfortunately, pretty irrelevant - of course hopefully you'll all get on very well, but in practical terms, it's not as if the parents get (or indeed should have) a veto, so it'll be a make the best of it scenario regardless.

Married nearly 30 years, together over two years by the time of our wedding.
My parents met PIL at the wedding and never saw each other again (PIL now departed).
I’d resent having to alter my holiday plans to meet someone I don’t know, they are right, holiday time is short. I imagine they have a full itinerary and don’t want to spend half a day making polite chitchat.
Don’t take it so personally, it’s not a snub or anything!

Because her time would be the time it takes to fly to the states and back and getting from the airport to where they live, whereas there time is just taking an couple of hours out of their busy schedule. Or not even that if OP joins them for a meal they will be having anyway.