The much admired and beloved Swiss conductor Marcello Viotti succumbed to a stroke two decades ago at age 51, leaving the music world in shock. Today, two very talented children of his are keeping the Viotti flame alive. At 35, his son Lorenzo has established himself internationally as a maestro of sharp technique and keen imagination. His big sister Marina, 39, is a mezzo-soprano as remarkable for her rich, luscious timbre as for musical and dramatic class (you should see her Carmen). This year, the sibs celebrate New Year’s Eve together in Zurich’s new production of Die Fledermaus. Marina mimics the cracking voice of an adolescent in the plum role of the bored, spoiled-rotten Prince Orlofsky, for whose amusement the batty attorney Dr. Falke (Yannick Debus ) stages a diabolically convoluted prank. Golda Schulz is Rosalinde, a society wife who goes to Orlofsky’s ball disguised as a Hungarian countess; Regula Mühlemann sings her maid Adele, who turns up in one of her mistress’s dresses, pretending to be a Russian actress. Mostly, the joke’s on Rosalinde’s husband Eisenstein (Matthias Klink). For good measure, there’s a dopey tenor in the mix named Alfred (Arthur Owens). No party for him. He sits it out in the slammer. Anna Bernreitner directs. —Matthew Gurewitsch