Man With Dog
This is William Pouter's portrait of Vetinari with his faithful pet dog, Wuffles. (Although there are rumours that the Patrician carefully nurtures a man who is his exact body double, for specifically stated reasons such as sitting for portraits, or attending long-winded civic functions where it is important that the Patrician be seen to attend).
Normally on display in the Royal Art Museum, for most of the events described in Making Money, there was presumably an empty space on the wall and a face-saving notice hastily pinned up there apologising that the portrait had been taken down for cleaning.
The picture had in fact been stolen to order (Sir Reynold Stitched gloomily admitted that this is an occupational hazard of running an art gallery) and when encountered in Making Money, is in fact hanging on the wall in Cosmo Lavish's study as part of his obsessive and some might say, lunatic, drive to become Vetinari and take his place as Patrician.
Cosmo succeeds so well in becoming as one with Vetinari - at least, to his own satisfaction - that he actually has intelligent conversations with the painting. Although the advanced blood poisoning brought about by a gangrenous finger might have something to do with this particular heightened state of consciousness.
Following official recognition of Cosmo's claim to the Patricianship, and a greater interest being taken in the private lives of the Lavish family (if only to recover several tons of missing gold), it is possible the painting has been recovered and is now back in its rightful place.
Although Sir Reynold must surely now be thinking of enhanced security measures, as that's twice now that a major artwork has been stolen from his Gallery.