MIL has forbidden DS to call for his friend when we visit

You must be local if they all go to same school. Can't you organise playdates with the friend without needing to use MIL house?

It's ridiculous that you think this amounts to saying a child can't be entertained in those circumstances, as an absolute. This particular child isnt. These are the facts as you've been told them.

OP I'd make it clear that DS will not be taken for hours to be bored and nor will you undertake the work of entertaining him for the whole time so the in laws can have their way whilst doing nothing to facilitate.

I’d reduce the frequency and/or length of visit. What a long and boring day for a child. I’d continue letting him visit his friend but advise him not to come into grandparents garden with her. Then arrange for his friend to visit him at home some times.

It is very rude if he brings neighbours kids into his grandparents house, especially when he isn't the only visitor. Maybe if they were minding him for a day or something but not while visiting with family, and especially not if other cousins etc are there.
So what if his cousins are younger. You can bring a colouring book or lego or magmatiles or something for him, like you would visiting anywhere that a child would be bored. It sounds very entitled that you think his grandparents should entertain him while the whole family visits. Complaining that you gave to mind your own child while visiting is unreasonable.
And thr in and out of houses must be annoying to grandparents...... if they have specifically said not to call there and you tell him he can then you are being deliberately rude.

I would cut down on visits and set up play dates for your 6 year old instead.

Once a month visiting grandparents who from their demands sound pretty controlling and who don’t focus on their grandchildren as actual little people but rather just there to serve their needs is more than enough.

Iiwm she'd be told, politely, no.

But I would say to DS no bringing your friend round or in/out between the houses and not to be there all day.

I am from an older generation, but I do think that this is quite rude. Your inlaws want to spend time with their grandchildren and I know my parents wouldn't have wanted other people's children in their home.

Yes it is your - or your DH's - job to entertain him - because it's rude! Just arrange seperate play dates. Or agree a pattern (so once every couple of months or something) - your MIL wants to spend time with her family together.

The PILs sound like self-absorbed mean-spirited people. This isn't some random kid - it's their next door neighbour who happens to be their grandson's friend. Unless there's some massive backstory, why would anyone NOT cultivate that relationship, never mind good relationships with neighbours when there is an actual shared interest? There is absolutely no warmth or humanity in the PILs' attitude, and they will ultimately find it self-defeating.

My godson's grandparents hated their DIL and made a point of being frosty to her, while their grandson was very much subjected to a 'be seen and not heard' attitude. I once went for lunch with them all at their place and it was torture. The DIL is now dead and the grandson, nearly 21, hasn't spoken to them in years.

There are some obvious, logical ways of setting some ground rules in a compromise.

(however, I also decide when and how long with stay with family. If it's too long a day for them, leave earlier or arrive later. Or go less often.)

OP I can kind of see why the in-laws might find it a bit rude, but I can also see your point that they don't engage with him and it's boring for him. I think it would be pretty rude to accept their hospitality and then do something they've explicitly asked you not to. But I also wouldn't want to make DS sit there bored, because it will ruin his appreciation of these family visits.

Is there any way you can explain the situation to the neighbours and then, when the afternoon is dragging on and DS is bored and wants to go next door, you make your excuses and leave, then call on the neighbours and take the kids to the park (or maybe they will invite you in) and DS can play with the friend for a few hours and you and DH can watch while you chat. (If there's somewhere to grab a coffee nearby, all the better). Alternatively, just go home when DS starts getting bored. It's really not nice to make him stay somewhere where there are loads of people but no one's interacting with him. It's not really like entertaining himself at home.

If I go visit family then my kids don't go play with the neighbours. It's just rude, unless suggested by the hosts.
Particularly if their cousins are there! The age gap can't be that big if your son is only 6, surely you can see the value in him interacting with younger family members?

I can also see why you in laws wouldn't want to see kids coming in and out of their house, including kids they've never invited in the first place. I'm surprised you don't.

I agree.

That’s a long day my children would get bored unless there were activities for them to do. I’d try to hold it off by entertaining him but in the last couple hours of the visit I’d let him. Your ils can dictate who comes in their garden though.
My in-laws used to get bothered if dc were on their phones/watching tv but we were there 2/3 nights it’s impossible/uncomfortable to stay in visitor mode for several days

When we were kids, one of the highlights of seeing our grandparents was being allowed to call for and play with the little girl (more or less our age) who lived next door. It was a real treat to have a new friend. We loved it and it kept our grandparents connected with their neighbours, which is always useful. Don't understand the mentality of thinking this is bad thing!

If it keeps them off screens and physically playing with each other that's very precious. Could you have a conversation with in laws to understand what exactly the issue is, maybe there is a win win.

Because it's something their grandchild enjoys, maybe? 🤔

If it keeps them off screens and physically playing with each other that's very precious. Could you have a conversation with in laws to understand what exactly the issue is, maybe there is a win win.

I guess it's your in-laws right to not have the neighbor's kids in their yard, if that's what their complaint is about. But other than that, I think that's the parents' decision, not the grandparents. I guess I'd say more information is needed here.

Sorry OP, but you lost me at your last sentence. We have a 5yo and a 1yo and both work full time. We're both exhausted and we still play with our own kids. That's parenting.

My kids are the only grandkids in both sides and seem to manage fine without younger ones to play with. If your inlaws don't have toys - take some! And organise seperate play dates with his bestie. It's really not that hard.

I think they aren’t being unreasonable to not want his friend in their house, that needs to stop. I don’t see the harm in your DS playing next door though as long as it’s not very time and just for a small amount of time like an hour. If it’s longer and more often that’s more of an issue. I don’t get the bit about you saying you and DH have to entertain him though, surely yes you do as he’s your DC. It’s your responsibility to keep him entertained and play with him.

Sorry, just saw the bit about them coming into your in-laws' garden. I have to say I can understand a bit more of why your ILs don't want this becoming a regular thing, were they asked if the kids could come over? (But even then there is a pressure for them to say yes). I think best thing is for any play dates to not impose on your ILs at all. I love having kids over for playdates and also remember how sad I was when I watched one of my flower borders of seedlings get absolutely trashed through innocent play/running around. They shouldn't have to be responsible for anyone else's kids in my humble opinion.

Sorry OP I might have missed this - where you say the kids are between the two houses do your DS' friends ever pop over to your in-laws' to play, or are the playdates always at the friends' house? The only way in which I could see this being unreasonable is if your in-laws are being forced to host play dates at their house. Assuming they aren't then absolutely encourage DS to do to their house if he is feeling ignored.