Here is the documentary regarding Their Imperial and Royal Highnesses Prince Georg Friedrich and Princess Sophie von Preußen entitled, Das Erbe des Kaisers. Click here to watch the entire documentary. (in German)
With many thanks to Princesas de la Realeza for finding and publishing the video first. 🙂
The Royal Correspondent 
Oh, how I wish I spoke German! I watched it any way and drooled over the homes and the tiaras. These two are a charming couple. Do they live in any of the schlosses shown in this documentary?