Apologies if this is a complete red herring, but here goes anyway.
You have Benjamin NICHOLLS in Rollesby in 1841, aged 9 with his parents Samuel and Frances?
This is the family in 1851 [which Ancestry have transcribed with the surname of the family above them on the page - Nellums]
Low Street, Rollesby
Samuel Nicholls 48 Ag Labourer Rollesby
Frances Nicholls 44 Wife Clippesby
Benjamin Nicholls 19 Ag Son Rollesby
Elizabeth Nicholls 12 Daur Rollesby
Robert Nicholls 11 Son Rollesby
[Census ref: Class: HO107/ Piece: 1807/ Folio: 243/ Page: 15]
I couldn't find Benjamin in 1861 or 1871, but going on the information from the 1881, I looked for the children in 1871, and found this family:
Coast Guard, Elmer, Middleton, Sussex
William Brown head 39 Coast Guard Norfolk
Martha Brown wife 27 Norfolk
Frederick B Brown son 5 Suffolk
Alice E Brown daur 3 Suffolk
Charles D Brown son 1 Sussex
[Census ref: Class: RG10/ Piece: 1114/Folio: 69/ Page: 11]
I don't have an explanation, but it is a curious coincidence of names ages and birthplaces for the Brown children in 1871 and the Nichols children in 1881.
I can't see the Brown children in 1881, or the Nichols in 1871.
The births of Frederick and Alice Nichols should have been registered in Woodbridge district (which includes Felixstowe), but FreeBMD doesn't show either with any variation of spelling for Nichols.
I would normally say 'hope this helps' at this point - but I'm afraid it doesn't really
.