Over a decade ago when I used to live in El Paso, Texas I went to an elementary school that was like 95% Hispanic and I was the only kid in the entire school that has blond hair. But if you pass by any elementary school that is predominantly WASP, blond haired children are a dime a dozen.
Let’s imagine your parents are farmworkers and speak only Spanish. All you hear at home is Spanish. Your friend’s parents are farmworkers too so they all speak Spanish. And with your friends you speak Spanish. At church the padre or minister conducts the service in Spanish. You go to any store in ‘Mexicano’ downtown Watsonville or East Salinas and they all speak Spanish too. But as a parent you don’t worry about your kid speaking English.