The Census image has John and Kate with a son Tom.A. aged 20. Actual image is hard to read but probably should be 2.
Marriage;
John Thomas SCUFFAM/
John Tom SCUFFAM indexed as both

December 1898
Boston 7a 895
On same page Kate HARLOCK
Birth;
Tom Arridge SCUFFAM
March 1899
Boston, 7a 434
This would make him 2 by 1901 Census

The 1901 census has John.L. Scupham indexed, it is definitely a T when you look at at it.
1901 Census
214 Clarks Passage
Boston Lincs RG13/3044/178/31
John.T. SCUFFHAM, 24, mar, horse shunter for Railways, born Hoberts Bridge, Lincs
Kate, 22,wife, born Leake Lincs
TOM.A. son, born Boston ( says 20, could be 2)
Now to look for John.T. in earlier census
