Catherine was alive in 1861, aged 56, so findagrave.com is wrong!

Name:    Catherine Lea
Birth Date:    29 Sep 1805
Birth Place:    England
Death Date:    18 Apr 1856 (should be 1866)
Death Place:    Cheshire, England
Cemetery:    Harthill Chester Churchyard
Burial or Cremation Place:    Harthill, Cheshire
Has Bio?:    Y
Spouse:    William Lea
URL:    https://www.findagrave.com/mem...

Mary Ann Lea
Event(s):
Birth:  About 1832   Burwardsley, Cheshire, England
Marriages:
  Spouse:  John Brereton  Family
  Marriage:  DEC 1863   Tattenhall, Cheshire, England

Born Bunbury, 1832 according to 1871 census

Name:    Mary Ann Lea
Gender:    Female
Baptism Date:    10 Jul 1831
Baptism Place:    Harthill, Cheshire, England
Father:    William Lea
Mother:    Catherine
FHL Film Number:    1655829

Name:    Mary A Brereton
Death Age:    89
Birth Date:    abt 1832
Registration Date:    Q1 1921
Registration district:    Chester, Cheshire
Volume:    8a
Page:    443

BRERETON, Mary of Laurel Bank, Tattenhall, Cheshire, Widow, died 26 March 1921.  Probate London 11 June to John Bate and John Darlington, farmers and Clara Brereton spinster.  Effects. £704 10s. 

Aged 7 in 1841

Aged 11 in 1851

Name:    Job Lea
Gender:    Male
Baptism Date:    7 Jul 1839
Baptism Place:    Harthill, Cheshire, England
Father:    William Lea
Mother:    Catherine
FHL Film Number:    1655829

Name:    Job Lea
Registration Year:    1858
Registration Quarter:    Oct-Nov-Dec
Registration district:    Great Boughton, Cheshire
Volume:    8a
Page:    229

Name:    Job Lea
Birth Date:    1840
Birth Place:    England
Death Date:    3 Jan 1859
Death Place:    Cheshire, England
Cemetery:    Harthill Chester Churchyard
Burial or Cremation Place:    Harthill, Cheshire West and Chester Unitary Authority, Cheshire, England
Has Bio?:    Y
URL:    https://www.findagrave.com/mem...