Thank you Frances and Jean. I suspect that they were buried in a common grave.
Regarding the need to ensure that Catholic children were not regarded as illegitimate I suspect that Sarah's oldest living son who could not accompany her to Australia [over the age of eight] when he married in Ballaugh Anglican Church shortly after the 1841 census may have been in Ireland on the census date being married, returning for an Anglican marriage to ensure the legitamacy of any children.