Over a million people have responded to an invitation to a coming of age party for a girl in rural northern Mexico after her parents' video innocently asked "everybody" to attend ended up going viral.

A local event photographer posted the video describing a down-home 15th birthday party complete with food, horse races and local bands to his Facebook page, which is usually dedicated to announcing weddings, baptisms and other events in a rural corner of the northern state of San Luis Potosi.

But the video was picked up dozens of times on YouTube, with each version getting hundreds of thousands of views. It has been seen by millions, sparked tributes by musical stars, become the butt of jokes, and drawn sponsorship offers by companies.