Thank you for your reply. The "Margt Pierson" in the will most likely my Margaret. I cannot find the will you speak of though. I was told that they changed the spelling of the name from Pierson to Pearson. There seem to be so many records for Gelling but Pierson seems to be a mystery although the family married into what seems to be a very prominent family in the Isle of Man. On the lawsonsiom.freevar.com site, there are a few wills for Pearson and the one that intrigues me is for a Eunice Pearson:
PEARSON, Eunice 1825 Bra E 1 0106425

None of the Pearson wills have been transcripted to the site so they are not available to see. John Pearson who married Margaret Gelling seems to have been born about 1780. Margaret died 27 Nov 1848 in Buckingham, Quebec, Canada and is buried with their son William 1814 – 1844.