http://www.vanhoogstraten.org/ is a wonderful photograph collection from the Archives of the Stichting Familie van Hoogstraten, Amsterdam. UNFORTUNATELY THESE PICTURES ARE CURRENTLY NOT AVAILABLE (January 2011), SO THE LINKS BELOW THIS ARE NOT OPERATIVE.Louise Dorothea Adriana van Son, an aunt of Georges van Son married into the van Hoogstraten family; the result of this happy occurrence being that there are photographs of Georges' parents and other relatives in existance - presented on this historic Website.
The various photos were taken in Holland, France and apparently England. What I find most interesting, as it helps to explain Georges' language skills to some extent, was that Louise inscribed photos to her father in English, and Stéphane inscribed a photo to Louise in English. This must have been one of those truely multilingual families.
The one photo of Jean Chrétien was taken in Java in 1897; they were also international travellers?
A photo of Nathalie van Son-Kamarowsky, Georges' mother, dated 1912 was taken in St Petersburg and the other, dated 1913 shows her in Cossack dress.
On the page of François van Hoogstraten (XIII-H), there is a picture of François with Stéphane and Nathalie, as well as a second picture of François with Nathalie. Here Nathalie is described as "Nathalie Gravin Kamarowsky-van Son", and the family estate is described as " "Doubrowa", Efratowa, Gouv. Orel, Kromy District, Rusland".
All the pictures on the Stichting Familie van Hoogstraten Website can be clicked-on to obtain enlarged versions.