Mary states the the 'birds of paradise' flower is the state flower of California during the Independence Day party. This is incorrect, however the 'birds of paradise' is the official flower of the city of Los Angeles, where the movie takes place.
Despite all the references through the move none of the leads are Mexican or Mexican related. Camilla Belle was born in the USA to a Brazilian mother and USA father. Alexa PenaVega was also born in the USA to a Colombian father and a USA mother.
The trivia item below may give away important plot points.
The hospital that Maria goes too after the car accident is called Linda Vista Compounding Hospital. This hospital is in fact in LA but is also a haunted hospital that was featured on the TV show Ghost Adventures (S03E06). The hospital has since been demolished and is now a block of apartments.