There is an army pensioner named Hugh O'Donnell in St Helier, Jersey, in the 1841 census. Born Ireland circa 1786. He has a wife Mary aged 40 ( much younger - a second wife perhaps?) and a number of children including a son John aged 9.
Army pension records show that he was from 101st Foot and was admitted to pension in 1817. I can't find his discharge papers to confirm whether or not he had previously served in 47th Foot.*
There is an 1849 merchant seaman's ticket for a John O'Donnell born in Jersey on 5 May 1833.
* now found his 1817 discharge papers indexed as Hugh Donnell. Born Drumkirin, Leitrim circa 1786, enlisted in the 101st in 1806. So it appears that he never served in the 47th Regiment.