Mary Ann COLES may have been the Mary Williams who was buried 14 Sep 1843, St Botolph without Bishopsgate, whose funeral was somewhat costly by comparison.
In the hunt for Mary Ann's birth, I happen to notice that a Mary Coles was baptised 5 May 1747, and recorded in the register of St Mary Le Bow, London immediately before Ann Williams - Ann being the sister of Joseph Williams:
Sadly, this baby was buried on the 6 Oct 1747, but led me into seeing if the couple, William and Mary Coles, had other children:
William Coles Baptism 11 Mar 1734 - Burial 10 Jun 1736 St Mary Le Bow, London
Mary Anne Coles Baptism 24 Jun 1736 - Burial 3 Mar 1737 St Mary Le Bow, London
Thomas Coles Baptism 20 Sep 1737 - Burial 24 Sep 1737 St Mary Le Bow, London
Charles Coles Baptism 7 Nov 1738 - Burial 8 Apr 1739 St Mary Le Bow, London
Elizabeth Coles Baptism 8 Jan 1739 St Mary Le Bow, London
William Coles Baptism 15 Oct 1742 St Mary Le Bow, London
Mary Coles Baptism 18 Aug 1743 - Burial 7 Feb 1744 St Mary Le Bow, London
Martha Coles Baptism 11 Mar 1744 - Burial 3 May 1799, aged 54 St Mary Le Bow, London
Mary Coles Baptism 5 May 1747 - Burial 6 Oct 1747 St Mary Le Bow, London
[Thos Coles Burial 8 Nov 1747 St Mary Le Bow, London]
Sarah Coles Baptism 16 Feb 1748 - Burial 7 Jul 1749 St Mary Le Bow, London
Mary Coles Burial 11 Apr 1782, aged 79 [1703] St Mary Le Bow, London
Clearly not the family I'm seeking, but enough to have me looking a bit deeper around the area…