Moving this discussion to the Adobe Digital Editions forum.
The Nook can connect to more than one computer. My suggestion is to connect the Nook to your son's computer, then, using his ID, transfer the ebook(s) to your Nook. However, don't try to move the ebooks from the Nook to your computer - that will produce an error when ADE compares the ID in the ebook to the ID on your computer. Be satisfied that the ebooks are on the Nook....