To not want SC to move in as adults?

I understand that, I meant more in terms of if he can get his ex to go to mediation he might be able to get her to see what is in it for her if he has more access.
I would also consider not overpaying on maintenance and putting the extra he pays now aside for the kids/buying for them directly instead as it means she would have less financial gain from keeping them.

The courts will not force teenagers to visit - they can make their own minds up. That ship has sailed.

Why aren't you saying 'We would love you to move in with us as adults, but you need to understand that it would be a mutual agreement between adults which would involve commitments on your part. You would need to be in education and or work, and there would be ground rules for behaviour too. Obviously we won't ask anything of you that we don't do ourselves, but as adults you will need to be responsible for your actions.'??
Also, has your partner had any kind of mediation with his ex to try and resolve the fact that he sees so little of them? It sounds as though if he can find a way to put it to her as a benefit to her she would be more inclined to send them. His parents have passed, and the kids are only 12 and 13, he has zero excuse for not pursuing this through mediation or the courts now. What is his reasoning?

Thinking about this again, I think you need to convert it into actions now, rather than threats for when they're older.

I think I'd say to DP that unless they spend significant time at yours from this point onwards, you will not be living with them after they leave school, even if that means you split up. In which case your DP would potentially have to house both kids as well as having his younger child(ren) part-time.

I'd be asking DP to be clear with his kids and his ex that they need to come to yours x amount of time from now on, if they want a possibility of living with you part-time when they're older (I wouldn't agree to full-time). And for DP to tell his kids he will be coming to collect them at x o'clock every other Friday/Saturday (or whatever you agree) - and then he turns up at that time and offers to help them get their things together and into the car. I think you have to really chivvy kids along sometimes and show you mean business, even at age 12/13 (mine are around this age and they're good kids but they still need nagging to get in the shower, do homework, go out of the house etc).

He does this every fortnight for a few weeks in a row. If they still refuse to come to yours regularly, he makes it clear to them and his ex that this decision means they will NOT be living with you guys when they finish school. And you make it clear that if he tries to move them in anyway, you will be splitting at that point.

I disagree with posters saying this is so far off and a non- issue now.

We all know the state of play for young people in the UK, and that leaving home - even when working - is increasingly harder. It will not have miraculously improved in 5 years time.

OP, you are prudent to be thinking about this now. It sounds like they are a convenience to their mother now, but once the associated funds stop, she will be offloading what sounds like a pair of lazy losers onto you and your household. From your description of them, they are on a fast track to unemployment without prospects and qualifications.

Nothing, but nothing would make me want to be involved with this, let alone share mine and my child's home with any of it. Think very carefully about marrying this man is my advice. He sounds weak and things will only get worse.

16 is not an adult. I would be insisting they either are in full time education or an apprenticeship with part time college if they want to move in, non negotiable.

This.

They won't be adults at 16 and he's done the absolute bare minimum of parenting for years.

He needs to prioritise them.

What do you both say when this sort of topic comes up?

Maybe you need to speak to your DH and then hold a joint 'come to Jesus' meeting why you lay out your actual current concerns about the way their lives are going - they are old enough to understand this by now - and very much to keep it real about what life living with you as young adults would be like (including not being your equals, you having young child(ren) so behaviour/language/visitors/loud noises after bedtime from adults has to put that first, them having to pay rent, your car not being their car, it having an upper age cap etc).
Strongly encourage them to move in sooner rather than later during this meeting so you can't be accused of backing out of your promises that you would have them if they wanted to come.

I think OP is right to be worrying about this now. Yes of course teens say daft things. But the worry is here that the OP will suddenly end up living with two young adults who she and their dad have had little influence on, and who have been given no ambition or boundaries by the parent they do live with.

Whilst also bringing up her own young child(ren).

I've seen a few threads on here where an older teenage / young adult step child has moved in and caused trouble - but also has little education or job prospects so it's almost impossible for them to get their own place.

I don't know what I'd do really OP. Probably have a very serious conversation with your DP that although you care about his kids and want the best for them, you won't be having them move in with you as young adults unless they're genuinely in full time work or training, and even then you'd expect them to move out after a year or two. And that if he does let them move in with the expectation of lounging around the house, you and he will likely be separating at that point. And that he needs to be really clear about the above when his kids bring it up.

But children without boundaries never change for the better.

This sounds like hell on earth to me, the only redeeming feature is that the kids are still young and so it may be so much pie in the sky.

Definitely let everyone know now that this will not be happening, that you will not have these bone idle adults lazing around your house all the time because that's what it'll be: you'll get home from work tired out to find the house a tip, they've eaten all the food and are bleating 'what's for dinner?'. You'll hate them then.

So make it plain they must study, work hard, get qualifications and get on in life. You won't be supporting them to do anything else. And what's this insane idea of nail clients coming to your house for their appointments? What would your insurance complany have to say about that? No, no, no.

They're not going to be 'influencers' (God, what an ambition!), they're not going to be anything unless the get themselves into gear now.

I know! “Her current plan is to do nails from
home” WTF? Since when did we take a 13 year olds current life plan as gospel and make our own life plans based on it?!?

I can’t believe people are talking about a 12/13 year old like this. Basically making out they will be a leech and a sponge for life based on some stupid comments that were apparently made. My aim at 13 was to go into the Big Brother house. I ended up going to uni and got a total of three degrees and have supported myself since I was 18.

I mean I'd never turn away my kids or stepkids whatever age they are but you do you

Yes we had downsized thinking they were alll on their way. Thankfully my exh was decent and happy to have them mostly.. my DC got it luckily we had lots of weekends away on our own ! Its so hard stepparentjng. I didnt find it easy and internalosed all the anger which was mostly to thrir mum for jyst bailing. Verh similar ti your situation in thst once the makntenance went and she couldnt control everything she the gloves came off.. and you cant undo yesrs of poor.. in your case... or toxic in mine.. parentung. It tales the poor kids years to fix it. My BF was still running around after her hortible DM for decades after an abusive childhood. As a stepmum its judt loselose.. thqnkfully i love my DH to bits and we gog through it as a team. Good luck whatevrr you do but im guessing ig might just be dumped on you.. it was with us !

I don’t think this will work.
They won’t particularly want to be “independent”, or house share - that’s far too much work. Neither will they think it sad. On the contrary, they will see it as a good plan - no responsibility, no bills, accommodation all sorted, etc. They will see it as perfectly within their rights, and nice, to have mummy and daddy looking after them.

Again though this is on DP to set expectations with them. Regardless of their mothers input DP needs to let them know that as adults in someone else’s house they will have no control over anything - if they want to decorate how they want and have bf/gf staying then they need to be renting their own place. There’s still many years for DP to change their mindset from relying on you to figuring out how they’re going to become independent. You can’t control how their mother parents them, but you can protect yourself by telling DP that unless he puts some serious effort in and sets boundaries then the wedding will be postponed/cancelled.

Honestly as a bread winner I think you'd be mad to get married especially when you have your own child to consider.

If they lived here we could embed a work ethic, we could set expectations, and we could support them. That’s much easier to do for young teens than full grown adults.

Their father isn't embedding anything he hasn't already. They've got their work ethic set and it's that you work and support them. Also known as failure to launch. They are literally telling you this and their father agrees and you're afraid to rock the boat of entitlement but you know the shit show that's coming at you. That's why I say they show change now, as in chores and willingness to work, and get jobs when they can legally work. If they don't, tell your live in that game's over and he's going to be living with and supporting his older kids, not you. You're going to have to prepare for that because he's a lazy parent who does what's easy rather than what's best for them.

Once the kids can get to your home on their own, the whole “mum might keep them from me” is pretty much over. That’s fair enough when they’re toddlers but I can’t see her having much sway now.

It’s very difficult to enforce the ‘they have to stay in education until they are 18’ rule. We regularly have children younger than that drop out of education- mostly to work- under 16 and in practice after fining etc there is not a lot they will do.

"Both kids have started saying that when they’re adults, they’ll move in with us. They both want to stop school at 16 and become influencers, basically, or if they have to work, do as few hours as possible (their mum and stepdad work 10hrs a week and are both apparently disabled)."

"They've dropped into conversation that they’ll be living with us as adults repeatedly over the past few months, it’s clearly accepted as a done deal by their mum."
Don't let that go by without a response! Every time it's mentioned you bring up jobs - what do they want to do, what sort of jobs there are round your way, what qualifications they're going to need, they need to be aiming for a job that pays enough for them to live on, you don't want to only be able to afford a bedsit when you're 30, yadda yadda yadda. Crowbar it into the conversation if you need to, but make sure 'jobs' and 'working' and 'earning' are drip-drip-dripped into their ears. Laugh lightly at the idea of being a social media influencer 'that's like being a pop star, a handful make a living from it and everyone else just wastes their life wanting something they're never going to be'. Be brutal about 'influencers'. If they counter that their mum has a great lifestyle only working 10 hours point out (be brutal!) that that's because their dad gives their mum money for them, that lifestyle cannot be financed on 10 hours work. Don't they want more for themselves?

"My partner’s response is that we’ll cross the bridge when we get to it but that our door should always be open (which I agree to when they’re children, but not as adults, without conditions)."
Nope, it'll be too late by then. His Ex is clearly planning ahead for the end of child maintenance, and you two need to too, or she'll completely outflank you. He needs to give his head a wobble and do right (belatedly) to his children by harping on about jobs, working, earning, qualifications. And he needs to start that ASAP. If it puts them off coming, so be it - that will spike his Ex's plans to offload them at 16 onto you. She won't like that and may actually start to see that the only way she'll get rid of her little cash cows when they're no longer bringing in child maintenance for her is to have them actually earning, and that can only be good for the children.

You are right to be paying attention to this now, because if you don't do it now you'll be ambushed later.

Oh, and don't marry him - keep your house yours. Because if you marry him in the present situation, your house will effectively be forfeit to his ex-wife. So don't.

I think moving in adult DSC who have no intention of having productive lives would significantly negatively impact your children's lives.