accident-2
Explanation
In this comic, a child asks their mother: "Mom, Dad said I was an accident. You know you can tell me." The mother firmly responds: "Nope!"
In the third panel, the mother explains her reasoning: "The goal was to make the worst possible thing we'd been talking about something quantity-related." The final panel reveals what "the worst possible thing" actually was, as the child reacts: "That is so much worse." The mother offers: "Here's a diagram if it helps to make it sound scientific."
The joke hinges on a parental misdirection. Normally when a child says "Dad said I was an accident," the implication is that the pregnancy was unplanned -- an emotionally sensitive but relatively common revelation. The mother's denial isn't that the child was an accident, but rather she's reframing what the "accident" was. Instead of the pregnancy being unintended, the parents had apparently been trying for a specific number of children and got the wrong quantity -- but the comic implies the actual story behind the child's conception is something far more embarrassing or disturbing than simply being unplanned, something so awkward the mother needs a diagram to explain it. The humor is in how the mother's attempt to soften the blow backfires spectacularly, making the child realize the truth is "so much worse" than simply being unplanned.