Hi Vicki
I'm a rescue worker for Cats Protection. That's means I'm an amatuer but I have dealt with many situations like this.
I would say the thing to be avoided at all costs is upsetting mum at this delicate stage in kitten rearing. Mum cats have been known to abandon kittens in times of crisis and may not accept them back again. An hormonal queen is a highly strung thing - much like human mothers - and heaven know how their minds work!
She's chosen that spot as her nest for reasons only she knows. Best leave her to it while the babies are so small and so vulnerable. You really want to avoid any possibility of having to hand rear them.... honestly, you really do!
Milly's Mum has given some great advice. Make your home appealing and safe and mum may move the babies inside herself as they become old enough to start weaning. I have picked up whole litters from people's sheds that have been suddenly moved there by stray queens seeking a new and safer nest for their growing babies. So there's every hope your mum will do the same.
The weaning process is also much easier for mum if there's a ready supply of fresh, clean food to hand.
A nice box lined with a few towels next to her usual feeding station is a good thing to try.
If they still haven't been moved inside by around 4-5 weeks, I'd think about trying to trap them. They will no doubt be very active by that age and easy to catch with the right bait. If caught by age 5 weeks they will be hand tame in a couple of days. Older than that and it will just take longer. Much over 6-7 weeks and you may need help from some experienced tamers. But even so generally they don't know how to strike out until around 8 weeks so it's only a case of ignoring hisses and spits and as much handling as you have time for. If you do need help, CAT77 are very good at that kind of thing if your local CP doesn't have the experience. They may even loan you a confinement pen for the kittens if you need one. Certainly read the excellent advice on the CAT77 website.
