I had not picked up on Fredersdorf losing weight, that's interesting. I've always imagined he put some weight on after 1732, when moving in with the Crown Prince and the making-up-for-lost-time table Fritz set. And of course we have no Fredersdorf paintings from before then to tell us, so that's just my headcanon. He might have been stout in 1731 when meeting Fritz! Though his age plus his peasant background plus the army plus the cost of food makes me think otherwise.

But Fredersdorf losing weight in his later years, probably related to his health issues, is interesting. Noted for fic purposes!

cahn, you remembered correctly, that Fritz starts commenting on putting on weight in 1731, at Küstrin. In late 1756, when the war started, he decides that food is for weaklings, and his loved ones start freaking out, as described by this thread. By 1758, Catt is startled by the change from when he last saw Fritz in 1755.