Maria Kusche and Sylvia Ferino-Pagden have shown the influence of Sofonisba’s Portrait of Margaret of Savoy with Dwarf (c.1595) on two of Diego Velazquez’ pieces: his Portrait of Prince Baltasar Carlos (1632 Boston, Museum of Fine Arts) and his 1656 Las Meninas, particularly in the way Velazquez poses a vessel that passes between the figures. (Kusche and Ferino-Pagden, Sofonisba Anguissola Renaissance Woman, (NMWA, Washington DC, 1995) 95; See also Daniela Pizzagalli La Signora della Pittura Vita di Sofonisba Anguissola, p 208.)
I wonder if Velazquez’s Prince Baltasar Carlos was also influenced by another of Sofonisba’s paintings, one recently attributed to Sofonisba, her Portrait of the Princes of Savoy, the First Children of Carlo Emanuele e Caterina Micaela (1589, Torino, attributed by Alfio Nicotra in Incontri, Oct, 2013).
Velazquez centered the baldish baby heir the same way Sofonisba did. The dress Velazquez gives Prince Baltasar Carlos angles backward just like the right figure in Sofonisba’s. Then the folds in the dress of Velazquez’ dwarf on the left echo the folds of Sofonisba’s prince on the left. The arms of the figures in both portraits reach toward the center, as if creating an invisible circle. The drapery above and dark backgrounds behind the children are similar in each. The luxurious carpets beneath both have similar horizontal bands framing the bottoms of the portraits. Both pieces are highly detailed in gold.
Even if we cannot be certain whether Velazquez copied Sofonisba, we do know who came first. Her Princes of Savoy preceded his Prince Baltasar Carlos by forty-three years.
Lady In Ermine: The Story of A Woman Who Painted The Renaissance 