All I know is that my family is from el salvador. And we have always cooked birds on that day. My grandma had lots of foul on her land....they actually call it "Dia de Chompipe(sp)" It's some flightless bird.
Either way I like it because I get 4 day weekends. And the whole family gets together and gets sloppy drunk , full and basically beat each other . La familia
But funny my ancestors are both Indian and some sort of European immigrants that settled in El Salvador.
So Anytime I get time off work and a big feast of all kinds of food, tamales, pasteles , atole etc.. Is ok in my book. I ain't changing now