Family members had to open a path for the girl through dozens of reporters and photographers snapping her picture so she could reach the Mass being held her in a field in the state of San Luis Potosi.

A large billboard saying "Welcome to my 15th birthday party" with Rubi's picture towered over the tents and tables filled with food.

Thousands of people came from across Mexico for the celebration, a traditional coming-of-age party similar to American "sweet sixteen" parties, in which Mexican families often throw big, costly bashes so their daughter can be princess for a day.

"I came to see if they would give me a dress for my granddaughter for her 15th birthday in May," said Victoriano Obregon, who had come all the way from the northern state of Coahuila.