I am a male Erin, born in the 1980s in the US. The name is consistently listed as a feminine name, although the birth stats do show some usage for boys through the 1970s onwards.
Does anyone know much about the usage for boys? Is it a mistaken spelling of the name Aaron like some people say, or is there an actual more direct reason tied to the spelling of Erin itself. Personally I see them as two completely different names with different histories and roots.