Which raises the question: What is standard English? Since it [If I was the only boy…] doesn't sound "perfectly natural" to me, does that mean I don't speak standard English? Is standard English something that nobody really speaks, but it's a sort of average? I won't say it's wrong, but I would never use it, and would mark it for correction if I were [sic] editing a written piece, then probably allow the writer to overrule me, after discussion.