sad-3
Explanation
The comic shows a child running to his father, exclaiming: "Dad! Dad! Mom was making terrible moaning sounds in the night! What happened?" The father awkwardly improvises: "Oh, uh, that uh... she was... very sad about something?" The child then innocently responds: "She was sad three different times!" The father, caught, simply concedes: "Oh yes."
This is a classic "overheard parents having sex" joke. The child has heard sounds from his parents' bedroom and innocently asks about them. The father's panicked, stammering excuse -- that the mother was "very sad" -- is a transparent attempt to provide a child-appropriate explanation for clearly sexual noises. The punchline lands when the child helpfully specifies that she was "sad three different times," inadvertently revealing the number of sexual encounters (or orgasms) that occurred. The father's defeated "Oh yes" in the final panel is the look of a man who realizes his cover story has only made things worse, as the child's innocent elaboration has now made the situation even more awkward and specific. The humor comes from the dramatic irony -- the audience understands what the child does not -- and from the way the child's naive precision transforms an already uncomfortable moment into something mortifying.