So happy for you! It sounds like you have been doing some research and your vet really sounds great (in that she called every day to check on your Gretel). Having a good relationship with your vet is definitely a good thing! That being said, I too agree with the masses that one should wait until the pups are at least 12 weeks old - it truly does make a difference - I have seen the differences firsthand with my Jack and Izzy; however, under the circumstances which you have described, I think maybe it is best to get little Princess Sophie home with you and Hansel.
Get ready for the spoiling to begin! Oh, and I agree with the OP about these little ones - sometimes I think are worse than skin kids. Oh and what Guinness' mom said about yelping when they bite and then take their scruff in your mouth - it truly does work. Can't wait to see pictures of little Princess Sophie!