To feel disappointed DS was left out at his nan’s b’day party by his cousin?

You can't expect 13yo to host and invite him along. If he wanted to joint the children to run around and play, he should have joined them.

My 19 year old wouldn't be seen dead playing with kids 😂

I think maybe you are looking too deep into this. He is an adult.

Bloody hell woman, give yourself a bloody good talking to. Your son is an adult. If he is feeling rejected and hurt it is because you have molly coddled him and kept him as a baby because it suits your needs. He is a man not a boy.

My “technically” adult sons might prefer playing in the garden to talking to 60yo uncles they don’t know very well, but it would be a “adult leader” taking the ball to the park, setting up goals, leading the youth astray mucking around way - not a “playing with peers” way.
The 19yo is a child who needs a bigger boy to hold his hand and include him but the 11yo is a grown man who needs to make sure everyone is included - it’s just a weird attitude.
At 11, a 19yo is barely different from a 50yo - they are both adults the way that a Shetland and a shire are both horses. You just think “oh, there’s a horse” and carry on.

Your son will be interacting with adults of all ages in the world of work, so you need to encourage him to start now.

He’s a fully grown man who can vote, get married and buy a house. It is his issue and no one else’s.

How strange that you think an adult would want to play games with a load of children?

Why couldn't he just speak to the adults?

Sorry.
Cousins possibly would not of seen the need for social interaction with your son, because the age gap does affect the play. Why didn’t your son step in and say (assuming they were playing football) ‘Do you need a goalie?’

We attended a family gathering at Easter, we were reluctant guests because we wanted to be at another event. Our son (20) stuck between children aged from 5-13 who were running riot and his adult cousins (30+) and my husband’s siblings.

He took the decision to entertain the children in the garden with a treasure hunt and experiments with coke and mentos (I’m sure you know how this turned out). Of course that experiment caused issue with the mothers but the kids loved it. Our son is now their hero.

Op was he diagnosed with social anxiety?

did they also look at autism?
As he could be more than anxious.
communication issues and rigid behaviour.
sensory issues?
stims?
friendship issues.

I think you and him are seeing him at 19 as a young child not an adult. It’s not for a child to invite him to play. He could have gone to them and asked what they were doing and got involved.
I think your general worry about him is projecting on the situation. He’s done nothing for 11 months since finishing college and just started volunteering. How does he fund his life? Lots of teens who are autistic work eg McDonalds my dd worked at from 16 pt, the lads who didn’t want to speak to anyone were in the kitchen.
I’d encourage him to start to pursue a diagnosis he’s an adult it’s not for you to look into.
If he like playing with younger kids then youth work is an option - lots of summer camps hire teens in this country or abroad. At 19 last summer my dd was at camp America responsible for a cabin of kids and organising activities for all the kids there.

Your DS needs to learn how to interact with people who are older than him. That's who he's going to be working alongside and living alongside. If he feels "excluded" and has "lost self-esteem" because children are ignoring him, then he's still identifying himself as a child, not an adult. As one of those "ancient" post-50-year-olds he "didn't know" and therefore apparently couldn't engage with, I can categorically say that having a mixture of generations to talk with is refreshing. At familial social gatherings where I often meet for the first time young adult children of my siblings and cousins, I'm more than happy to engage with them and learn about how they see the world. His problem is he didn't even make a minimal effort to do that, and from what you've said, you facilitated this sense of isolation for him. Give me a break with "he has social anxiety". That's BS. It's not a disease, but simply one of the post-modern self-identifying as a victim labels that is ruining today's society. I'm sorry, but I very little sympathy for you or him. You both need to grow up.

Why do we think it odd that a fully grown man wants to play with children you seriously need to ask?????

Im assuming there is no husband and you are treating this fully grown adult man like a toddler so he never leaves you,

But, if anyone is responsible for including him, it's the other adults in the room, not the children.

I thought this too. I think you need to teach your son some social skills/coping techniques for these kind of situations. The whole “not comfortably with an unfamiliar adult” thing is not good at his age - that is literally the definition of almost any party or gathering he willl go to. Teach him some “safe” topics of conversation with people he doesn’t know and ask other (adult) family members to help him beforehand if that’s appropriate. But it’s certainly not the responsibility of an 11 year old - that’s incredibly unfair on your nephew.

I remember being that 18 year old sandwiched between kids and much older adults at family events, it just happens and yeah I ended up hanging with the older people as I wouldn't have wanted to run about playing with children, even young teenagers as the gap is too wide by then. If anything I would play in a baby sitting sort of way, not be actively included in games at that age gap.

It's an awkward mix of ages but no-one was rude not to include your son, except perhaps the adults who didn't take the time to engage him in chat.

Why does he not work he should have had a saturday job and have been working for 3 years, you should be encouraging him to work..

‘Play’ and the age ‘19’ do not belong in the same sentence .

My 12 year old thinks 18 year olds are ancient.... Dont be so blabby ridiculous op. I get he's your PFB but honestly, even you cant think that is normal.

^^ This

Exactly its odd that you want an adult male to play with children, very odd

technically he's an adult
No he's an adult
He could have kids / mortgage / full time job / be fighting for his country.

No words! Hes a fully grown adult, ..stop treating him like a todler, ..and why is he sat next to you, why is he not out with his mates or partner

Your son is 19 and an adult. It would be weird if he was out playing with an 11 year old!

@BoldMaker73 You said that your son spent most of the evening with you. Do you also sit out of the mingling because there are friends of the older generations involved in chatting and you don’t know them very well? Were you mostly on the sidelines for the evening also?

I do wonder how you would have felt if your son at 11 years old had been held responsible for not including a 19 year old visiting family member in his games? Would you have considered that reasonable?