that's a lovely photo to remember this family by. The broody has done a fine job there, raising a large clutch to independence, and looking after them this long. I would guess she has taught them well how to free range; evidently at least one has mastered hiding already!
wonderful news - and photos!
For some weening takes place then but my broodies typically stick with their chicks longer than that; 3+ months is not unusual here, when the chicks start to drift away on their own rather than being driven away by their broody.
she's waiting for the last eggs to hatch then; she'll give up soon if the hatched chicks are already on the move; at 3 days old they will need food and water and she knows it.
If you've got a pet carrier/dog crate, could you add that to the coop for them? or knock up a brooder out of a few bits...
The chicks don't smell, but her broody poop does.
If you've seen the chicks I guess she's moving around, so not still sitting waiting for the last egg(s) to hatch, in which case I'd bring them into your protected area if she doesn't. They will come for food and water so it shouldn't be difficult...