Where you start in life doesn't matter, but how big a jump you make in improving your lot does, and that's something that's entirely up to you. Please lay off the Rawlsian stuff - it doesn't square with the things I've observed in my own life. Nor does it square with the experiences of many of my friends that started life out poor, and chose to make something of themselves.
At this point, some might say, "you didn't earn your brain/parent's money/etc." I say that's nonsense, because the entire idea of "earn" arises in order to distinguish real people who choose to act toward a goal from those that choose not to. To do that, we have to look at adults - lots of them, ranging from bums to billionaires, across time and professions, on and on. Then at young adults, then at small children (to fully see the contrast with adults). Choice is the crucial thing here: nobody could arrive at the idea of "earning" or "deserts" or "justice" by studying newborns or fetuses.
Relying on "earn" (which depends on the idea of choice and free will, as I've indicated above) in a statement intended to undermine the idea of choice and free will is bogus.
EDIT: I am making some serious points here. Disagree all you want in comments, but downvoting me reflexively does not refute my argument.