Handwritten into the chart, not by the original author.

According to Grigonis798, he was Major General David Robertson of Her Majesty's Indian Army (born 1840 in Bengal, India).

In May, 2010, I was contacted by Richard ‘Zippy’ Grigonis, who was writing a biography of Ivan T. Sanderson, a descendant of Amy Boileau and David Robertson. According to his information there was a fourth child, Stella Winifred Woodthorpe Robertson, who married Arthur Buchanan Sanderson. I’ve included the details from Grigonis in the cards below, and the full quote of the information he sent me is included in the card for her daughter, Stella, just for interest.