Sylvia, in case you haven’t already seen the information in the link below, see what you think. It looks as though a descendant of a John Callister b 1846 (who married Louisa Caine), son of a William Callister, has worked backwards on the Callister line and claims that this William was the son, b 1817 Santon, of John Callister / Eleanor Cannell.

www.familysearch.org/ark:/61903/2:2:3MH8-K5M

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If you ignore the fact that this tree probably involves guesswork, and just use it to see what has been included relating to the possible parents of John Collister b circa 1777 and of Eleanor Cannell b circa 1776, there might be something there which proves helpful.

The tree-submitter has suggested that Eleanor Cannell was the daughter of Robert Cannell and Eleanor Hingley, giving children as John b 1773 and Eleanor b 1776, but doesn’t seem to have spotted that Robert Cannell had died before Eleanor’s baptism (noted as posthumous) and that Eleanor nee Hingley/Hinley remarried soon after to William Crellin, going on to have several more children.

The parents suggested for John Collister b 1777 are Robert Callister and Mary Watterson with Rushen as birth parish. I can’t see any evidence for this though.

Jean C