I am a direct descendant of Anne Isbister, born circa 1827, in Belsay, Orkney. Ann was the daughter of Magnus Isbister, her mother was believed to be Margery. There were two Ann Isbisters born around this time (one in 1825), but it is believed that Ann was probably named after an older infant sister, who died very young. I am still researching the Magnus Isbister line.
Anne married Richard Sandercock (who originated from Cornwall, England)in Sunderland, Co. Durham, England and had one son, George (my great great grandfather) I have been unable to trace her since 1862, the year her husband died (in Sunderland) George would have been around 4 years old at the time of his father's death.
I would be interested to see if the two families are linked in any way and hope this will be of some interest to you.