You don’t often see portraits of famous Romans as children, but the Uffizi has this interesting bust, believed to be of Nero, detailed above.
Also of interest in the collection is this possible portrait of Nero as a child.
Unrelated, but of interest is this painting by Antonio da Correggio, popularly called Correggio. He was was the foremost painter of the Parma school of the High Italian Renaissance. He was responsible for some of the most vigorous and sensuous works of the 16th century. In his use of dynamic composition, illusionistic perspective, and dramatic foreshortening, Correggio prefigured the Baroque art of the 17th century and the Rococo art of the 18th century. He is considered a master of chiaroscuro.