It looks to have a happy ending. These two survived to (almost) adulthood.

Both of the young from this nest (the one we tracked) are flying. I have not seen them both off at the same time, but photographer friends have.
They still return to the nest, and a meal is delivered from time to time. But now they have the next phase, hunting on their own.

The image above is the younger of the two. Still mystified how the big ‘brother’ just goes off on his own in the air.
With luck we will have a few more photographs before they disappear for good. Food, and then travel (South America maybe) is next.
A very happy ending! Beautifully sharp photos.
Thank you. It looks that way. Some others not so lucky. We are heading out early AM to check the nest. They might still be spending the night there out of habit.