The given statement above is an example of an old wives' tale. An old wives tale is a belief that is regarded as superstition or with no scientific basis or evidence. In the sentence above, it is an example of a simple sentence having one complete clause. The phrase "like the proverbial cat" is a phrase that describes the subject "she".
Hedda is more bound by convention and Thea is braver.
The tone of the poem might be considered as calm and even sweet at some point. it could be understood as an numeration of positive things about a puppy and it's good influence it might have in a person´s life.
I can only think of protest, demonstration, rally, and strike. You could just add peaceful to the beginning of the word.