Advise Welcomed

Bluebelle I really admire you for doing all that travelling. Id be too exhausted to do anything with them. I do envy those of you with good relationships with their grandchildren. I try, but I don't seem to be the kind of granny children want.
BTW like others I feel its hard to justify your position SMC when you ask a strangers child.

I don't really see what the problem is unless his kids have no grandparents of their own. If they do they can go to their grandparents when you have yours to visit or at any time that suits them. It's a bit weird when you've known your grandchildren from birth yet have only known his for 3 years, you can't possibly have the same bond. Besides which how does their mum feel about them going to stay with a virtual stranger. I also understand why you took a friend for the youngest, I used to regularly take a friend for my eldest and regularly wished I hadn't bothered lol other people's kids can be a nightmare.

Very tricky situation, I get that its up to you which and how many children you have and can see the other side with children in a family being treated differently, sorry I have no useful advice other than there needs to be more communication about the situation . I feel for you, try not to dwell on it but sort it sooner rather than later.

I can understand why you took on the 4th child as a left out child is more work than two who play together. How well do the 6 and 8 year old know you? do they get on with your bio grandchildren? Even if they do I just don't see how you can have them all. The only thing to do is to discuss this with everybody and explain you just can't do it, it has nothing to do with loving them all just physically impossible.

well I dont think you can really say that 5 is way too many and then have 4... that will raise eyebrows!

IMO once you are minding more than 3 youre minding a "pack" and its the same whether its 4 or 10!

Would have been more sensible to hook up some local playdates for the little one if youre worried about him being lonely rather than citing numbers for your reason for not wanting 5 and then pretty much inviting a different 4/5.

I dont see why your GCs cant have time alone with their bio family anyway so surely there was no need for the numbers excuse in the first place?

Step siblings can do some things together and some apart, not everything has to involve everyone!

I am a bit confused by the arrangements. I absolutely get that you having 5 kids of varying ages is tricky! But you have elected to have an additional ' unknown this year so 4 will be OK.
Fiancé is not keen (or his ex is not keen) for kids to be cared for by 'strangers" but appears upset when you do not invite them. Sounds like communication is poor! Did DD want a week on her own with fiancé & now they have his kids? Seems like you all have not got this blended family thing sorted. If it was me I think I would say firmly and clearly to DD that I was happy to have any combo. of DGCs / DSGCs but only in batches of 4 or fewer and offer dates I have available! Leave the sorting out of who is coming when to them!

This is a tough one, as you say 3 children is enough, for me 5 would be impossible, if you split them into 2 groups then you have all of the travelling to do twice.
Could you all have a family holiday together somewhere? Then you get to see all of the children together, but with the parents to share the burden/ joy.

I honestly don’t have a solution to this one, sorry but I hope it works out.

Well I can understand if you have had a strangers child to stay why there is the misunderstanding It doesn’t seem very fair to have a non family friend ( making four children) but not have the two step family kids although I can really see why you don’t want five children for a week I ve done that and it’s blooming hard work very very noisy and excitable and I m not sure how I managed
I don’t really understand the mixed messages he doesn’t let his children stay away as he is over protective but is upset they haven’t been invited ??
Do the five children live together have bonds and get on well As the 7 year old gets left out at yours couldn’t you have the 6,7 and 8 year old for a week and the 10 and 12 for a different week That’s what I d do
I just flew out to get my 12 year old for a week then flew back for a few days to bring my 15 year old back for a week as she didn’t want to be left out but couldn’t manage the first week All that travelling was a real phaff but I m aware that next year at 16 she won’t be wanting to come so felt I needed to make the effort

It’s difficult isn’t it. 5 kids is a lot to ask biological or not. Actually 4 would be too especially as you don’t know this friend of your grandsons?

I don’t know what your family actually want? For you to treat the step grandchildren equally? I get that. It’s often more difficult because they have yet another side of the family to consider too. Eg does their mother agree to you taking the children?

Assuming all good there maybe you suggest you have them all but not at same time? A week for 3 and another for 2 plus friend maybe? A mix of biological and step?

If this doesn’t suit all I can suggest is to be honest and let them know you just can’t cope with 5 kids including the practicalities of getting out and about. No reason they should think you are being unreasonable.