I haven't made the connection yet but my Richard Steele was living with your John Cain's Renshant family in the census of 1841. Richard Steele's mother at the time was married to Thomas Cain and were living at Maroon in the 1841 census. See below.
I'm not sure if Thomas Cain may have been a brother or cousin of John - Thaomas is the second husbadn of Richards mother Christian (Kinley/Steele) Cain.

I've been sent the census information via members of the
isleofman.com forum. Donna Douglas and Brian Lawson have been very helpful and are very happy to pass on information they can find. I've found a lot of information on Familysearch.com too.

In 1841 I list 2 separate families, as Christian Cain's (nee: Kinley, 1st married Steele) son Richard Steele is living apart from Christian with a Cain family at Malew at this time.

1841, Malew, district 7, page 3, Renshent
John Cain, 50, farmer
Ann, 28
Thomas, 23, farmer
John, 18, baker
Jane, 16
Robert, 13
William, 9
Richard Steel, 13, male servant, England

1841, Marown, district 3, page 18, Garth, cottage
Thomas Caine, 40, labourer
Christian, 35
Robert, 6
John, 1