I could see from other census, the Gillo, was sometimes transcribed as GILLS.

On the 1911 census

at 6 Churchfields, Salisbury.

James CAMPBELL, Head, Married, age 45, Naval Pensioner, born Plymouth, Devon (1901 census, His Majesty's Ship 'UNDAUNTED' in Devon (James Edwin/Edward CAMPBELL - Widower age 35 ) married Minnie RAYMOND, March Qtr 1903 Newton Abbott)

Minnie CAMPBELL, Wife, (Married for 9 years) age 46, born Plymouth, Devon

George GILLS, Boarder, Married, age 25, Bootmaker, Gloucester, Glos.

Eva GILLS, Married for 3 years age 23, born Pillowell * South Eastern edge of the FOD above Lydney.

Harold GILLS, Boarder, age 11 months, born, Gloucester Glos - seems to tie up with Harold George GILLO - June 1910, Winchester (GILLO family tree on Ancestry.com)