By the time of the final episode of Malcolm in the Middle, "Graduation," Lois had given birth to baby Jamie, and with Reese moving out and Malcolm (hopefully) heading off to college at Harvard, the boys unanimously decide that their little brother should grow up free of the kind of worries that had hung over their own lives. As such, they decide that the time had finally come to remove the "nuclear option:" Evidence of the absolute most horrible thing they ever did, something so awful that they could have used it to destroy the entire family if one of them had ever gotten too far out of hand.
That evidence? A chest X-ray. In a flashback, we see that the boys (all played by very young kids in this scene) manipulated the X-ray to make it appear that their mother had lung cancer, and we see Lois and Hal wailing in despair at the result. Why on Earth would they do such a thing? Well, because they had all gotten crappy report cards, and they needed a distraction so that their parents would sign them without question.
Yep, that is ... just horrifying. The show left us hoping that baby Jamie would grow up to go a little easier on his mother, but that final episode also revealed, in its closing moments, that Lois was pregnant again, and none too happy about it. The poor woman simply could not win.
