Can you lower the dog house to ground level? If so, do it. Then, if you can create a temporary pen around it with chicken wire, that will give her a nice place to raise them for the first couple of weeks. Add a feeder and a waterer and you're all set - the hen will do the rest.
If you can't turn her chosen spot into a poult-safe area, you'll need to move her after the poults hatch. She will continue to sit from the time the first hatches until she thinks the last has hatched. I've had them sit 2-3 days after the first poult peeked out from under her. What you don't want happening during the time she is sitting, is for the already-hatched poults to fall out of the dog house, so if you can't lower it, you'll want to keep a really close eye on them when they are hatching and be prepared to return to the nest any poults that falls out. (Since the hen won't leave the nest during hatch anyway, you might attach chicken wire to the front of the dog house after the first poult hatches so they can't fall out.)
Moving is an anxious time. What I do is gather up the poults and place them in a box, then grab the hen and carry her so that she can see the box of poults. Even then she will be anxious and struggle to get away from me, but its worse when she can't see the poults. I set up the new area ahead of time so by the time I am transporting, as soon as I get there, I can set the hen down and lift the poults out of the box and she is good to go. At that point she is usually ready to stretch her wings and let go a poop she's been holding during hatch, and her next priority is to get something to eat and drink. The poults will watch and copy her, and she will frequently sit down to let them warm up under her. As the days go by they will spend less and less time under her and more time out exploring.
I keep the mother and new poults in a safe pen by themselves until the poults are about two weeks old. At that point, the mother is usually pretty sick of confinement and ready to get out and start teaching her offspring how to free-range. At that point I let them out during the day and they return to the pen at night, quite willingly.