Complex sentence: Shea grew up on the mean streets of South Boston; at the age of five he was beaten by two older children, spit on and left in a gutter.
Split into simpler sentences: Shea grew up on the mean streets of Southie and learned just how mean those streets could be at the tender young age of five. At the age of five Shea was beaten by two older children, spit on and left in a gutter.