One of the recurring themes in Mad Men involves lost children, children who have lost their parents, parents who have lost their kids. We see characters who were abandoned, orphaned, or simply didn’t get enough love (Don Draper included) who go on to pathologically treat their own offspring the own way, often without much awareness or self-reflection about doing so. Don was a lost kid who became a lost adult, though he's kept it covered it up with bravado and a good sell over the years, albeit with a few cracks emerging.
This “lost” storyline goes well beyond Don, though. Pete lost his mother, in part because of Bob Benson. [...]