grammar error!

<p>I just happened to be reading over my Common App. additional essay that I have already submitted to Vanderbilt, Harvard, Emerson, and UNC. I almost wanted to cry when I saw that I had written "a boy that" rather than "a boy who." </p>

<p>It's just incredibly annoying because that's the kind of thing I go crazy over in other's writing, and I can't believe I didn't catch it! Obviously I'm going to correct in the rest of my apps, but do you think it could potentially hurt me for the schools I have already sent it to?</p>