Although the author of that book claims that it’s doubtful whether this portrait represents Pitt (Ward, 1904: 124), he gives no reasoning or argument to support his statement, and the likeness to Pitt is striking.
The description of this portrait, filed under the heading of ‘The Right Hon. William Pitt,’ is as follows:
"Full-length as a boy, seated on the edge of a bank under a tree; red coat, white waistcoat and breeches, frill. Canvas, 51 × 43. Ex. O.M., 1878, No. 269 (Sir Coutts Lindsay)" (Ward, 1904: 124).
In 1878, this portrait was in the possession of a Sir Coutts Lindsay, but who knows where it is located today? I haven’t been able to locate another image of this on the internet, but I’d sincerely love to see it in person (please, not as a puzzle!).
The Right Honourable William Pitt the Younger (1759–1806) by Gainsborough Dupont, c. 1787-1790. It is located at Kenwood House, Hampstead.
If you compare Pitt’s slouching stance and the relaxed positioning of his hand in the portrait of him as a boy to that of the well-known portrait of Pitt by Gainsborough Dupont (above), you can really see a resemblance. Even the choice of setting in the portrait of him as a boy is something in accordance with Pitt’s personality: He is represented holding a book, and reading underneath a tree, something he was described as doing often when he could relax in the countryside (see William Hague, 2005: 213; Greville, 1911: 123; Ehrman, 1969: 594).
So, is this Pitt as a boy?
Ehrman, J. (1969) ‘The Younger Pitt: The years of acclaim,’ London: Constable, p. 594.
Greville, C. (1911) ‘The Greville Memoirs,’ London: Longmans, p. 123.
Hague, W. (2005) ‘William Pitt the Younger: A biography,’ London: Harper Perennial, p. 213.
Ward, H. (1904) ‘Romney: A biographical and critical essay with a Catalogue Raisonne of his works, Vol. 2,’ London: Thomas Agnew and Sons, p. 124.