Because I can dish it out, but I cant take it.
***
This song is about the death of 7-year old Katie Flynn. Hours before her death, Katie was the flower girl at her aunt's wedding, spreading petals down the aisle. As they left the wedding, they all got into a limousine and headed home. Martin Heidgen, 25, had had at least 14 drinks that night and his blood alcohol content (0.28) was more than three times the legal limit in New York (0.08). He drove more than two miles north in the southbound lane containing the Flynn family. Both the driver of the limousine, Stanley Rabinowitz, and Katie were killed instantly. Katie was decapitated and her mother held her head as rescue workers helped the rest of the family out of the vehicle.
The lyrics in this song draw many parallels to this tragedy. The first verse is seemingly from the mother's perspective, telling Katie to spread the petals and mentioning that she had one more night to be her mother. The second verse is arguably from Heidgen's perspective, referring to Katie as "My beauty supreme," and lamenting the guilt that crushes him. Four lines are sung towards the very end of the song and are nearly inaudible against the refrain. These lines seem to be from Katie's perspective and mention how she will never have to deal with loss herself, and therefore "should be the one laughing."
Some of the theories concerning the lyrics counting to 7: It was how old Katie was, there are 7 sins, and it is a number found throughout The Bible. (c)