Hi Karen,
Just to say the actual 1881 census doesn't list them as 'other' - the relationship column is just blank.
The 1871 census shows them as John and Eliza's children (as does 1861):
RG10/2916 8 9
Ogley Hay, Staffordshire
Walsall RoadJohn Jones, head, 44, Farm Labourer, b. Twycross Leicestershire
Eliza, wife, 45, b. Linn? Staffordshire
James, son, 19, Baker, b. Ogley Hay
Mary, dau, 14, scholar, b. do.
Elizabeth, dau, 12, scholar, b. do.
Ann, dau, 8, scholar, b. do.
Robert, son, 5, scholar, b. do.