A pregnant couple go to the doctor for a routine checkup. Afterwards the doctor sits down with them and tells them he has some bad news.
"Oh my gosh" says the mother, "is it serious?"
"No! Not at all, it's nothing serious." the doctor assures them. "All it is is that we've performed a screening of the amniotic fluid and the results that the fetus is going to be a bit German."
The couple look at each other, recrimination in their eyes. "Oh no!" Said the doctor, "the child is definetely yours. It's just something that can happen from time to time."
So the months pass and the baby is born, a boy, and everything seems to be going well but the boy never speaks. The parents are worried but he seems to be learning normally and the doctors confirm that his hearing is perfectly healthy. He enters into boyhood proper, around 6 years old, and aside from the lederhosen, pudding bowl haircut and stony silence he is indistinguisable from any other child.
One day his father is running late for work and frantically trying to get his son ready for school and lets the boy's porrige go cold before serving it.
The boy takes one mouthful, frowns, and says "Farter, this porrige is cold! This is unacceptable!"
The father's coffee mug shatters on the floor and he stairs at his son, agape. "You... you spoke!"
"Of course!"
"But... why now? Why haven't you said anything till now?"
"Up till now everything has been satisfactory!"