Hello, I want to get a North Face jacket for Xmas for my 14yo boy and I want to do it now before they sell out of sizes in the sale because oh my god the prices. And of course I don't know his measurements and he is at school. What I do know is that his sister's North Face is an XL and it is too big, but not absurd. Which suggests a L, unless the sizing varies wildly with sex. But he is only 14 and he is slim, so how can he be a L in men's sizing, where some men would be twice as wide as him? Anyone have a similarly sized offspring? Thanks for any help!