border collie / kelpie cross

[deeplybaffled]

My brother has just committed to adopting a 1 year old male from a local rescue. His wife works full time and he works shifts. Am I right in thinking this isn't the sort of dog that will happily stay alone in a terraced house and small garden, or am I just being an interfering older sister know it all? ? ?
Tbh, I'm much more worried about the dog than the house!
It's his first own dog although he has dog sat for multiple labs for fortnights over the last few years.
Are there any tactful warnings I can offer or should I just mind my own business, given that I've never owned a dog either and may have got this out of proportion?
Any advice welcome!

This is a combination of two bright working breeds. The dog is going to need a lot of physical and mental exercise. If he is considering doing agility or flyball this may work, but really this type of fog usually needs someone who can work with it a lot everyday.

It could be a really lazy chilled dog, but that cross at that age isn't one I'd consider taking on and I'm in all day and willing to do a fair amount of walking and training...

It's more likely to be a complete live wire than anything else.

It could work if they're planning on really spending an awful lot of time on it when they are in, but a walk round the park after being alone all day isn't likely to be enough.

Thanks. Not heard of flyball - what does that involve?