IMHO
In Uruguay, where I'm from, and in most of South America since we are mostly Catholics, we celebrate Christmas Eve with a big family dinner and await midnight, which is the beginning of the day Christ was born, to wish him a happy birthday so to speak...
It's also summer in South America this time of year, so we can celebrate with a big "lech?n asado" and all the trimmings, usually cooked outside with the warm weather...
At midnight we make a toast to the families gathered and to Jesus Christ...
Of course, we don't exchange very big gifts...we do that on January 6th, which is El dia de los Reyes Magos, Three Kings Day, who according to the Catholic religion, are the ones that bought Baby Jesus gifts, and therefore is when the little children receive their gifts...
Most of us immigrants have kept that tradition going...except we open the gifts on Christmas morning...and some believe in Santa Claus as the one that brings those gifts...
Here in Miami, the Cuban community has kept the tradition of Three Kings going with a big parade around that date...and some parents still give their kids gifts that day...
Is that a good explanation?
Merry Christmas to all!!
MQ