An interesting tidbit about Vadderung's name [possible Spoilers, White Knight and on]

After a short and precursory search of the subreddit's post history, I am certain that someone somewhere has pointed out the obvious "Thor's Father" translation of the name, but the suffix -rung also tickled me.

If you haven't yet made the connection, "Donar" is the proto-german name for Thor (as well as old english 'thonar', from which 'thunder' is derivative) and 'vader' (or vater/fader) is proto-germanic for father.

Taking it further, correct old pronunciation has a soft 'h' between the first and second syllables (vahd-hair-rung) making it possible that it is using the suffix '-hrengaz', a proto-finnic loanword to proto-germanic, meaning 'to turn'/'bent'/'curved', a very possible and purposeful reference to his dual nature. If we translate a little more openly, it also means winding (as in road), possibly hinting at his changing nature as he himself mentioned in Cold Days--

“Lad, let me tell you something here and now. None of us is what we once were. Everyone has a history. Everyone comes from somewhere. Each moves toward a destination. And in a lifetime as long as mine, the road can run far and take strange windings — something I judge you know something about.”

-hrengaz also devolved into the middle-dutch kringen ('around' or, interestingly, 'speedy') the source of the name Kringle in Kris Kringle.

Its meaning of curved and twisted also led to the naming of a kringle, a Scandinavian pastry that twists similarly to a pretzel. funny how pastries seem to be a motif for Harry.

Anyway, i find it fun to believe it was done on purpose.