Had a look on the Family Search website for this whilst looking for something else.
Came up with:
Frances Elizabeth Mundy
Born About 1810. Stratford Essex
Death 1 Jan 1885
Parents: Stephen Mundy & Ann
Marriage: Thomas Cox
21st January 1833. West Ham. Middx.
Cenus: 1881 - Forest Road, Kings Norton, Birmingham
It was submitted on the website
By: Andrew Lloyd
14 Howard Close, Fleet, Hampshire.
Could this be the Frances and Thomas you are looking for? The marriage is not in Aston but by the 1881 census shows that this Frances and Thomas moved to the Birmingham area.
Best wishes
Gill
Gill