Well it’s safe to that if someone observed the behavior of, or relationship between, cats and dogs: dogs seem always hungry with food always available and cats are always looking for food but not always hungry. Since dogs are more likely to be pets vs cats (especially in Greece back then) — this would also reinforce the satiated dog vs the scavenging cat. Which is the only element in the story that doesn’t directly appear to correspond with the images. Unless of course young trumpman is alluding to the empty bowl of food implying that the dog has eaten and is full.

The other possible interpretation of the images (that is slightly different in young trumpman’s story) is that the two animals could already be friends and are just playing.

I believe that young trumpman is using his own experiences and observations of these two animals to create his story.