...He also executed a variety of productions for the Boulton and Robinson families, the best known being two works now in the Art Gallery of Ontario: the full-length portrait done in 1846 of William Henry Boulton and the elegant and stylish Three Robinson sisters (Augusta Anne, Louisa Matilda, and Emily Mary). The latter painting, a gift to Emma Robinson, their mother, was commissioned in secret by Augusta’s husband, James McGill Strachan, and by George William Allan and John Henry Lefroy, who were soon to marry Louisa and Emily. It was presented on 16 April 1846 after Mrs Robinson’s return home from the wedding. The Boulton portrait, one of the foremost examples of the grand manner tradition in Canadian portraiture, is characterized, as are Berthon’s smaller bust and half-length likenesses, by tight brushwork, crisp delineation of forms, and fresh, clear color – hallmarks of French neo-classicism exemplified in the work of such artists as David, with whose style Berthon would certainly have been familiar. (http://www.biographi.ca/en/bio/berthon_george_theodore_12E.html)