Oil on canvas: 257.5 x 295.6 cm(!). Auctioned at Christie’s London, December 2012. That donkey is up to no good. Giovanni Francesco Castiglione (1641-1710), son and assistant of Giovanni Benedetto Castiglione (1609-1664). It is thought that many paintings which are ascribed to Giovanni Benedetto Castiglione are copies after him, or originals by his son.
More > Giovanni Francesco Castiglione at Matthiesen Gallery.
More > Father Giovanni Francesco Castiglione at Wikipedia.