Why wouldn't a non-Scot know what a 'close' is? "Brookside", a charming soap for all the family, charting the lives and loves of the residents of Brookside, er, Close, ran for about twenty interminable years and I'm pretty sure it was set in Liverpool.
I suppose it was a bit naive of you to mention it, OP, as it's the sort of thing that would very obviously appeal to her daughters, too, and you might have guessed her ears would prick up - but she's also a bit of a CF. I'd never assume my kids could attend, as she has done.
There are things I think it'd be tight for other children to be excluded from, and cases where it's entirely reasonable. Some things mentioned by PP are very definitely in the former category - if parents get Santa to come to a bloody pub, ffs, and don't have exclusive use, they should damn well let other kids come and see him, too. Or things in parks. Before Covid, if I stuck a quid in one of those shopping centre rides for my children, and there were other kids watching, I'd always tell their mums they could get in too. I think it's weird not to. I also remember being in a park in a poor part of town, and a mum very ostentatiously got her kids ride-on Lamborghinis and remote controlled planes, etc, out of her car and spent the next thirty minutes constantly shouting at all the breadline kids that they weren't to touch or ask for a go. I hope she got the clap. But I don't think it's necessarily tight to keep these particular kids away. I just think you'll have a hell of a job. Even if you hadn't mentioned it, there was always a chance kids would see them approaching (especially if you live in a block of flats) and be drawn to your place.
I also don't think eight is manifestly too old for 'Frozen' 🙄