General Notes
John was a Widower when he married Elizabeth Mollineux, both of St. Peters Parish, Bolton in Dec 1801. Ann is probably Ann the wife of John Mather of Atherton who was buried 12 June 1801 at Deane. Other spouses of John Mather that died are Ann of Preston who died Dec 1800, Betty of Eccles in May 1798 and Nancy of Winwick in 1794.
There are no previous marriages of a John Mather and Ann (or Anne) of Deane in the past 20 years, the nearest being Ann Eckersley, married 1775. Boton marriages are also limited. There is however an Ann Johnson married at Manchester in 1792 but she was still having children in 1805.
John and Ann Eckersley are of Astley. After John and Elizabeth were married, then had a Martha baptised at Atherton (but 16 years later).