Update:

I am inclined to rule out RICHARD RUSSELL of Devon (later Shrewsbury)

because

I have found a record which shows that JOHN RUSSELL briefly joined TS EXMOUTH (reason 'father deserted') before joinig the army (which ties in with his army record, which mentions a training ship). Further searches have found that he was admitted to SUTTON SCHOOL (linked to Woolwich workhouse) in 1872 with AGNES M RUSSELL (no ages are given). The reason given is 'father deserted, mother died'.

AGNES is discharged in July 1881 but I have been unable to trace her in 1881 or after.

Both are shown as chargeable to PLUMSTEAD. I think that the Plumstead Workshouse registers for that period do not exist anymore.

I am inclined to think that JOHN (possibly HAROLD in 1871, his middle name in later life) and AGNES are indeed the children of RICHARD RUSSELL (of PLUMSTEAD) and MARGARET MILLER (who I mentioned in an earlier post). There is a potential death for Margaret in Woolwich in 1872, which would tie in with their admission in 1872.

So where did RICHARD RUSSELL go after he left them? Abroad? Did he die?

And where is AGNES?