Two more in memorandums that I think relate to this family
I've written the memorandums under the child I believe it relates to in the 1841 census.

Census 1841 and Memorial inscriptions for St Marks, Malew (manxnotebook)

1841, Malew, district 7, page 3, Renshent
John Cain, 50, farmer
Ann, 28

Thomas, 23, farmer
(Sacred to the memory of Ann Jane, daughter of Thomas and Jane Cain, of Renshent, Malew, who departed ;this life 25 Feb 1855, aged 9 years & 8 months. Also the above named Thomas Cain, who departed this life 11 March 1890, aged 72 years.)

John, 18, baker
Jane, 16

Robert, 13
(Sacred to the memory of Robert, the third son of John Cain, Renshent, Malew, who departed this life the 7 Feb 1857, aged 29 years.)

William, 9
Richard Steel, 13, male servant, England