The 1851 Census shows a Ranald MacDonald 56 years old a farmer born in Canada and a Roman Catholic of Lancaster married to Mary MacDonald ditto age 57. Children Martin age 24, Allen 16 and Margaret 14. There is a Ranald and Mary recorded in St. Raphael's parish giving birth to Allan 1835, Catherine 1848, Donald 1823, Finnan 1846, Flora 1813, John 1825, Martin 1827 and Mary 1809. On one birth is shows Lancaster 7th Lot 9. I assume the Martin is yours but I can't say for certain all of the others are but are worth recording. If you need I can get actual dates of birth.