Thanks for the fantastic information! I spoke with my dad and he vaguely remembers a "Harry". He also remembers my grandfather saying that they were from around Hanover. I think that the Bernard you've described is my great grandfather. Additionally, Bernard had other children - Joseph, Harry (died as a child), Matilda, Anthony, & William. We have lost contact with all of their children.
I am very interested in following this back as far as possible. I know that you mentioned the LDS research center in SLC - I lived there for a couple years, but never made it to the Family Library. Do you know whether a local LDS church would have access to that information? I'd like to find out about a family crest as well.
I looked on the Jever DE website but my German has gotten a little rusty. Any help you'd be willing to provide tracing it back would be very appreciated.