Thank you all for your perspectives. Just to answer the most asked question: I have offered, of course, our homes, but they say they can't afford flights and spending money for all 4. DGS1 would've come over with his uncle and came back with all if us (did that in Feb the other way round). He can't have both on a plane and I believe that would be completely out of question for my DSD due to his young age and the fact that he's never been away from her for more than a couple of nights so far. We cannot afford 3 or 4 return tickets for them all to come during peak season, that's why we said we can only pay for one. With prices in the UK being what they are, his flight will cover a day out at an amusement park over here for 4 people. As to the "ageing grandparents" - I'm sure 48 isn't that old FGS! Plus we have friends and family with similar age kids over there, so plenty of company. Both DGSs are very different - DGS1 is social, engaged and loves to be out. DGS2 is a Covid baby, very reserved and doesn't like even going to the park. I guess, I have to accept the eldest will be missing out on various activities, since the young one isn't into anything and they tend to spend much of their time at home. Thank you for the advice! I will back off.