Once upon a time there were two sisters and one got married and one didn't. Or, once upon a time there were two piglets and one went to market and one didn't, or, one was straight and one wasn't. The point is, whatever they did or failed to do, they were a great disappointment to their poor mother. Luckily for them, the two sisters loved one another. When they saw that their mother was growing more and more unhappy, they proposed to her that she cut them in half and out of the two good halves make one splendid one. Their mother refused in high indignation, but she was so wretched that the dutiful daughters went to a surgeon. The surgeon obligingly sawed them in half, then interchanged halves and stuck them together. But there were still two of them. This was a problem. So they went back home and said to their mother, "Now choose the good one." But their mother was furious that they had even thought of such a scheme. "You did it to mock me," she told them angrily. "You are both bad children." When the two sisters heard her say this, the Good One wept, but the Bad One smirked.