Thanks for the chapter!
Ah, it's the ol' 'hardworking parent that never sees their sick child because they're forced to work themselves to the bone' trope.
As much as his non-serious attitude is grating, I have a feeling that it's the sort of humour that's really more for coping, really.
I mean, his wife is long dead, his child is terminally ill and he's been most likely coerced by what seems to be the Imperial family into some shady deal for medicine for his dying child.