With the stitching completed, I immediately got started on the finishing. It was really easy. I understand now why other stitchers say biscornus can be so addicting.
As for the cardinals, I think the eggs must have hatched, but I haven't actually seen the babies. The nandina bush that contains the nest has gotten a bit thicker since I photographed the eggs, and it's nearly impossible to see anything now. Getting a view of the nest at this point would require too much disturbance for the birds. I have seen both the female and the male back and forth a lot around the bush, bringing food for their offspring.