Emanuel Schikaneder heard this, he called down into the orchestra, "Hey, Mozart! That's no good, the music must express greater astonishment. They must both stare dumbly at each other, then Papageno must begin to stammer: 'Pa-papapa-pa-pa'; Papagena must repeat that until both of them finally get the whole name out. Mozart followed the advice, and in this form the duet always had to be repeated." Castelli adds that the March of the Priests which opens the second act was also a suggestion of Schikaneder's, added to the opera at the last minute by Mozart. These stories are not accepted as necessarily true
Mozart and smallpox both children's illness to contend with, the Mozarts spent a total of four months away from Vienna. They eventually returned there and were received in the Imperial court on 19 January, 1768. The Empress, who had by now lost three children to smallpox, conversed with Frau Mozart about the disease. The remainder of the trip was not especially successful. Leopold apparently misinterpreted a chance remark of the Emperor as a firm invitation for Wolfgang to compose an opera; this resulted in Wolfgang writing "La finta semplice". However, the opera went unperformed in Vienna; the singers and musicians did not like