"Regional accents are a major part of what makes American English so interesting as a dialect. Joshua Katz, a Ph. D student in statistics at North Carolina State University, just published a group of awesome visualizations of Professor Bert Vouxs linguistic survey that looked at how Americans pronounce words."
When parents use a language with their children that they don’t speak very well, but do so because of the language’s high economic status, they give their children a wrong example. The children will learn an incomplete version of the target language and may encounter serious problems in school. Sticking with the home language ends up being the more useful solution.