Based on the 1871 census, Isaac Gale was born approx 1818 in Bridgport, Dorset. Mary was born approx 1817 in St. Helier, Jersey.
They were living in Alderney in 1871 and had 4 children, all born in Alderney...
Anne Charlotte, born 11 Feb 1850
Henry born in 1854
Harriet M. born in 1860
Elizabeth M. born in 1857
In 1871, Anne was married to Thomas Palmer and they were living with her parents. They later immigrated to Canada.
Between 1871 and 1881, based on the census reports, Isaac and Mary moved to St. Helier, Jersey. Since she was born there, it is likely that Benjamin is related in some way to her.
Thanks for all your help and Merry Christmas.