Among the many early obituaries for Rand Paul’s presidential campaign that have lately littered the internet, one story has remained largely untold: the intensely personal father-son rivalry that helped derail the younger Paul’s presidential ambitions — twice.

Pundits and political writers have spent years speculating about the personal relationship between Ron and Rand Paul as the latter has sought to distance himself politically from some of his father’s more unpalatable positions. Publicly, of course, the two men express support for each other (often in the form of fundraising emails). And as Dave Weigel, the Washington Post’s Paul chronicler of record, has argued, the media’s evidence to the contrary sometimes seems manufactured. “[Ron will] joke that he’s still looking at who to endorse; it will be reported like Saturn devouring his offspring,” Weigel wrote in August.

But as I report in my new book, The Wilderness, Rand’s rise has indeed created some genuine intrafamily friction — and it started in the run-up to the 2012 GOP primaries.