Patty, it's not vital, but I want to raise the possibility that you'll do something besides visit family. I mention that because an Open-Jaw flight, even if it has a second segment on the more remote destination, can often cost the same as a direct roundtrip to one place like Frankfurt. Bad example, but if someone wants to visit the BMW factory customer center, or follow the path of Luther or Bach, you might go farther afield than Frankfurt. And you don't need to return to Frankfurt if you already have a ticket home from somewhere else.
To be clearer, we wanted to start a trip in Cologne, which you can't fly to directly. Lufthansa got us there for the same price as a direct flight, and since you can't get into a hotel at 9AM anyway, we were happy to arrive in Cologne at 1PM (from the US East Coast.) I think we drove across the Netherlands and flew home from Amsterdam.
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