Its like this.....
1st generation immigrants speak Spanish only.
2nd generation are fluent in English and speanish.
By the 3rd generation, English only.
Same with travelling to Mexico. I live in Texas and have always seen a large number returning at Christmas time and other times to see family and friends accross the border.
Speanish.
Cool. I’ve just invented a new language.
1st Gens are Mexican by birth.
2nd gens are Americans by birth.
Both will have various ethnicities coursing through their blood.
Over the years, it has been thus with REAL immigrants who want to assimilate and prosper.
As a volunteer reading tutor in a Nevada middle school, I have had teachers tell me that some fathers do not permit their kids to read, speak or write English at home as "Spanish is your heritage".