Charles James Whistler Hanson was the son of Louisa Fanny Hanson, said to have been a parlourmaid, and Whistler. On 25 June 1896 Hanson married Sarah Ann Murray. They had at least two, possibly three children. Their second child, Adrian Charles Whistler Hanson was born in London on 27 September 1902 and died on 4 April 1967 in Stoke Newington.
According to the Pennells, Hanson was adopted by Joanna Hiffernan and went to stay with her at 5 Thistle G
Whistler drew a picture, Charles Hanson m0587, of his son ca. 1876.
In fact both Joanna and her sister Agnes Hiffernan were closely involved in his care, and in 1880-1 he was staying with them in Thistle Grove Lane when Whistler was away in Venice with Maud Franklin, his current mistress. Agnes and her partner (and later, husband), Charles James Singleton, remained in close contact with Hanson at least until Singleton's death, when Charles Hanson was one of the executors of Singleton's will.
Whistler's brother William also acted as Hanson's adviser and supporter. Whistler himself provided Hanson with money and around 1887 he gave him a vacation job as his secretary. Hanson was at this point studying engineering at King's College, London. When he graduated Whistler helped him to find a job.
However, their relationship was not close, and he tended to expect too much from his son. Whistler did not attend his son's wedding in 1896, which unfortunately coincided with Beatrice Whistler's death, nor did he entirely approve, but he sent his best wishes and a cheque.
MacDonald, Margaret F., James McNeill Whistler. Drawings, Pastels and Watercolours. A Catalogue Raisonné, New Haven and London, 1995 .
The Correspondence of James McNeill Whistler, 1855-1903, edited by Margaret F. MacDonald, Patricia de Montfort and Nigel Thorp; including The Correspondence of Anna McNeill Whistler, 1855-1880, edited by Georgia Toutziari. Online edition, University of Glasgow.