Isabella Esther Cohen (unknown dates) was the daughter of the artist’s widow, Mary Ann Girtin (1781–1843), and Edward Cohen (1780–1835). She married John Turrill and they had two daughters. Annie Sophia Turrill (c.1846–1924) married Johnathan Holmes Poulter (unknown dates) in 1879 and was identified as ‘Mrs Poulter’ in Thomas Girtin (1874–1960) and David Loshak’s catalogue of Girtin’s watercolours (Girtin and Loshak, 1954), and Isabella Turrill (1838–1905) married James Oswald (unknown dates) and was known as ‘Mrs Oswald’ in the same publication. They both acquired sizeable collections of Girtin’s works from their uncle (Isabella Cohen’s brother), Edward Cohen (1816–87), who died without issue. The collection of Isabella Oswald was sold at Robins & Hine on 30 March 1905 (Exhibitions: Robins & Hine, 30 March 1905). Annie Sophia Poulter bequeathed her collection to her son, Edward Alexander Poulter (1883–1973), who disposed of the fine assembly of watercolours and drawings through J. Palser & Sons and Thos. Agnew & Sons.