Dear Mary I have just located this page and found all the info, etc, very interesting.
My family come from Gwinear, between Hayle and Camborne in Cornwall, and I have been looking into the family tree.The names John and George feature very heavily in our family and I’d be interested if the John Eustice which you are looking for might be one of them.
My Great Great Grandfather was called George (dob 17/4/1831), he had a brother called JOHN born 18/5/1834 - but as of yet I have found little else about him.Their parents were John Eustice (born cc 1806) and Jane Odgers who lived at Gwihian, near Hayle.Apart from George and John, there were also five girls Jennifer, Ann, Mary, Jane and Elizabeth.
Another JOHN Eustice features, born 1849, his parents were Henry Eustice (b cc 1808) and Mary ? (surname to be confirmed but possibly Shugg or Dunn).His brothers and sisters are Mary, George, Jennifer, Amelia, Elizabeth, William and Angelina.I am not sure of the birthplace of this John but believe it is probably Gwithian - his sisters were certainly married from Gwithian Church.
Again, not clarified, but it looks as though John Eustice (1806) and Henry (1808) may be brothers with a father named George.