Joke: There was four son's the oldest three had bright hair and bright eyes. The youngest son had dark hat and dark eyes. The father was on his death bed he asked his wife,"tell me the truth, is the youngest sun truly ours?" The wife responds with a simple yes and the husband dies.
Punch line: After he dies the wife breaths a sigh of relief and says "ohhh thank god he didn't have to ask about the other three.