The head of the Hunter family in 1911 at South Terrace is Mary Williamson Hunter(nee Gooding),wife of Ellis Hunter and therefore mother of JEL Hunter as per the biography linked by Rosie99.
So we can eliminate them as seemex has decided they are the wrong family.
I wonder if we are following a complete red herring with the suggestion that the house is in Littlehampton?
Seemex, are you certain that the girls are the family you are following? I presume they were sent back to England to go to school, when was that, do you know? Where were relatives of the family living in England then as the chances are they stopped with them in holidays?
First, the Littlehampton very well could be wrong as we've now eliminated that other Hunter family as being related.
As to the girls...I'm sure of them. They are my mother and her sister and Alwyn is their cousin. My Mother was born in 1911 and her sister in 1912, both in Hong Kong. They were sent to school in England from 1924 until 1928. The school was in Bournemouth, and they spent time with friends in and around that part of the country. They also spent time in Torquay on holidays.
Alwyn was born in 1908 in Shanghai and was also attending school. Two of his younger sisters also went to school with my mother in Bournemouth. I believe the Cock family ( Alwyn's parents ) also maintained a home or rented a home in England for some of that period.
In the house photo the girls appear younger than when they finished school in 1928 years later. I also have a couple of photos of a group that was taken in the same back yard and my grandmother was there. The only time they were all there together was in 1924 when she and my grandfather accompanied the girls to England to begin school. My dates are based on those facts.
In light of what has been discovered I think its maybe more likely that the house in the picture would be in the Bournemouth or Torquay areas and that the clipping threw me off.
