Can't find all the information I came across the other day but here's a bit of it-
Dublin Evening Packet and Correspondent, 4 June 1839: William Mitchell and Sons, Confectioner
Dublin Evening Packet and Correspondent, 24 Oct.1840: George Mitchell, Son and Successor of the late William Mitchell, Begs most respectfully to acquaint the kind patrons of his late father and the public generally, that ...
Dublin Evening Packet and Correspondent, 22 Apr.1843: ... Mr. George Augustus _, London, to Sarah _, second daughter of the late William Mitchell, Confectioner, of Grafton-street.
1843- George Mitchell, Confectioner to Her Majesty
Statesman and Dublin Christian Record, 13 Feb.1844: February 11, Mrs. George Mitchell, of Grafton-street, of a son.
Dublin Weekly Register, 16 Aug.1845: AMERICAN REFRIGERATORS. ... plate, 6xed within the inner lid. All applications for the Ice and Refrigerators to be made to GEORGE MITCHELL, Sole Agent for Ireland. No. 10. GRAFTON STREET. DUBLIN.
Dublin Weekly Register, 13 Feb.1847: SARAH MITCHELL, (Widow of the late George Mitchell), CONFECTIONER. No. 10. GRAFTON-STREET, is returning her most sincere and grateful thanks to the Nobility and Gentry of Ireland, kind and liberal support to her late husband respectfully informs them that ...
https://www.familysearch.org/en/tree/person/details/L51L-LD9 Robert M. Mitchell (submitted tree but no death details for Robert here)
Robert Mitchell (c1846-aft.1911)
https://www.irishgenealogy.ie/files/civil/marriage_returns/marriages_1876/11186/8098810.pdf (father- George P. Mitchell)
Irish Times, 17 Nov.1883: Robert Mitchell, 10 Grafton electoral division of the union ... street. confectioner and wine merchant; ...
Dublin Daily Express, 17 Nov.1883: Robert Mitchell, 10 Grafton street and 21 Kildare street, confectioner and wine merchant
Dublin Daily Express, 5 Mar.1885: ... The following were nominated ... Robert Mitchell, 10 Grafton street; ...
Whiskey Trade Review (Dublin), 17 July 1894: ... Mr. Robert Mitchell, the well-known wine and whiskey merchant of Kildare Street, and Director of the Metropole Hotel Co., Ltd., also connected with several other important Dublin industries, has, we are pleased to record, been appointed a representative ...
https://www.census.nationalarchives.ie/pages/1901/Dublin/Pembroke_East___Donnybrook/Aylesbury_Road/1284412/ https://www.census.nationalarchives.ie/pages/1911/Dublin/Pembroke_East/Ailesbury_Road/46251/Irish Times. 4 Jan.1934: Letters to the Editor ... if they can beat the record this firm holds. In the year 1805 it was actually in existence at 10 Grafton street, and the then owner (George Patrick Mitchell) was a great grandfather of the writer, so for almost 130 years it has been handed down ...
