In this poem Golden Cat, the sun symbolises the colour of the cat's fur, which is shining brightly. The sun also symbolises the provision of light apart from the other distinct functions that it possesses. The representation done by the animal is towards the sun which makes the fur shine.
It depends what they are talking about.
If they are talking about the bombing of 9/11 then the tone would be serious, sad, mad at the other country for doing what they did.
But, if they are talking about a major- fun holiday- like Halloween then the tone would happy, excited, energetic! It just depends what the topic the author is talking about!!
Hoped this helped you! :))