Leonard George Churcher (son of Thomas and Temperance) features twice in the 1881 census. One is at home age 19, a Ward Room Steward, Royal Navy, at Brockhurst Farm (see my recent posting) and also on board ship (HMS Assistance) as a 22 year old Ward Room Steward 2nd Class. (I think pay went up a bit in the Forces when you reached 21, so worth exaggerating...) I wonder if he was on board that night or not! The age fits the gravestone details.
The only Thomas that sems to be in the area in 1881 of about the right age to have died 1884 aged 25 is not a brother: Thomas CHURCHER, 21, stonemason born in Alverstoke, son of John CHURCHER age 59, a stoker at gas works. Living with family at 41 Henry St, Alverstoke