Hard same! Which is why I also am doubtful - unless someone finally gives us a direct citation like "see letter of Prussian official X/foreign envoy Y" - re: the handsome hussar story. On various levels and both sides. I mean, Fritz writes some of the most tender letters not in the first flush of infatuation (which we have zilch documents on, because Küstrin and Neuruppin), but years, even decades later. This does not sound like someone who'd have considered exchanging Fredersdorf for a random handsome guy at some point in the Silesian Wars. (And it would have had to be the Silesian wars, given when Fredersdorf died.) Also, since some of the earliest Fredersdorf letters are from the Silesian wars, I took this to mean Federsdorf wasn't with Fritz in the field to begin with, he was in Berlin keeping an eye on things from there, so how could he have been refused entry to the royal tent?

Now, of course, jealousy doesn't have to be rational and triggered by an actual cause. More often than not, it probably isn't. So it's entirely possible Fredersdorf thought he might get replaced by Mr. Handsome (if there is any basis to the story). At least replaced in the emotional sense, not in the professional, given the sheer number of tasks Fritz kept giving him. But somehow I can't equate someone this insecure about his status in Fritz' life with someone who has the confidence to stick with the German, keep alchemy as a hobby and keeps consulting non-Fritz approved doctors.

In conclusion: contemporary source, please, or I don't buy it.