Further to Annette7,s comprehensive analysis, which concurs with my own, I have a few more points
Are these the right Cresswells? The 1841 census mentioned does not name Cleophas, it clearly begins ‘Christo’, whilst it may well be Cleophas, that is not what it says.
Are the James Boxall and Sarah Boxall the subjects in the Boxall/Criswell marriage, if the ages are exact (and they only had to be to the nearest 5 years for the 1841 census) that has James aged 16 marrying Sarah aged 36. ( 19/33 and 13/39 are the extreme permutations using the 5 yr rule) if she was 21 in 1815 that makes her 47 in 1841 and 38 in 1832
Who is Mary Ann Boxhall? Is she James’ daughter or Thomas C’s, conceived before his death ( we presume he is dead) and delivered after the marriage. If the Thomas C I have found is the correct one he was 82 when he died, perhaps that is what killed him.
Mary Ann is in the 1851 census with a 40yr old James, her uncle!
Is 1841 Sarah Boxall 1841 James Boxall’s sister-in-law, sister or mother.
To be sister in law there would have to be two brothers both named James, unlikely.
Sister-possible.
Mother-possible but then Mary Ann would be James sister not his niece.
However, since starting this rambling, I have just found Thomas Criswell’s will on ancestry.com and it clearly names Sarah as his 'present' wife and mother of Mary, Antony, George, Edmond, John, Charles and Cleophas. So there is only the question now, did Sarah marry a toyboy, and who was TC's first wife?