The family portrait attributed to Johann Nepomuk della Croce was executed in late 1780 and early 1781. It is mentioned several times in the family letters. On 13 November 1780 Mozart, then in Munich for the premiere of his opera Idomeneo K366, wrote to his father: ‘[What’s happening] with the family portrait? – [how does it] look? – has [the portrait of my] sister been started?’. Leopold answered on 20 November: ‘You ask how the family portrait is coming along? – there’s still no progress. The reason is, I haven’t had time for a sitting and neither has the artist. And I won’t let your sister out of the house.’ There was still no progress on 15 December, as Leopold told Wolfgang, in part because Nannerl, he said, was still ill – which also explains his comment that he wouldn’t let her out of the house. Nannerl was better by the end of December and reported to her brother on 30 December that she would sit for the artist the next day; by 8 January she had been to a second sitting. There are no further mentions of the portrait in the family correspondence during Mozart’s lifetime. These letters make it clear that Mozart only sat for the portrait well before it was finished, and before he left Salzburg for Munich on 5 November 1780. He cannot have sat for the artist afterwards as he did not return to Salzburg in the spring of 1781 but instead travelled to Vienna, where he largely remained until his death in 1791. It is unlikely the portrait remained unfinished by the summer of 1783, the only time Mozart returned to Salzburg in the following decade.
The portrait shows Mozart and his sister performing a four-hand keyboard work – to that time Mozart had composed two four-hand sonatas, K381 (1772) and K358 (1773-1774); Leopold Mozart holding a violin, the instrument for which he was best known; and it includes a portrait within a portrait, of Mozart’s mother, who had died in Paris in 1778.
The Della Croce portrait is also included in the Mozart Portraits theme.