Maybe not, but it's definitely a symptom of a larger problem. Taken on its own, having the stereotypical Irish IRA member/drunk kid is a gag, but when you look at that plus the black kid named after slavery, the Asian girl named two single syllable last names (practically named Ching Chong), and a number of other semi-racist stereotypes in the books, it points towards somebody who is uncreative enough to avoid basing her characters on generic stereotypes or doesn't do any research before writing a character at best, and somebody who actually views those people that way at worst - a racist.