1841 census

Carrier on John and Maria's marriage certificate of Aug 1844

1851 census

name: Mary Anne Foulds 
gender: Female 
baptism/christening date: 26 Dec 1824 
baptism/christening place: BINGLEY,YORK
father's name: Thompson Foulds 
mother's name: Rebecca 
indexing project (batch) number: C00737-2 
system origin: England-ODM 
source film number: 0919130, 0919131 

Rebecca must be an error.  Thompson married Elizabeth Glover in 1820, and he was a minor then, so could not have been married earlier. Perhaps it was an extra-marrital affair.  There are no marriages for Thompson Folds and Rebeccas that fit.

Ann on the 1841 census, but Mary Ann is the correct name.  She was witness at Johns marriage.  Also, records her father as Thompson on her marriage.

Assumed died or married by 1851 and missing from census, but may have married.

John was a minor (<21) when he married Martha on 26 Aug 1844

b 1827 on 1841 census (Age 14)
b 1828 on 1851 census in Tong (so may be wrong)
b 1827 on 1871 census in Bingley, Carrier

There was another John Foulds born in Keighley, living with Israel and Mary in 1841.

Name    John Fowles
Gender    Male
Baptism Date    11 Oct 1826
Baptism Place    Bradford,York,England
Father    Thompson Fowles
Mother    Rebecca
FHL Film Number    0990537-0990539
11 Oct:  John son of Thompson and Rebecca "Fowles"
Abode Tong (when baptised)

or
Name:    John Foulds
Record Type:    Baptism
Birth Date:    24 Sep 1826
Baptism Date:    26 Aug 1827
Baptism Place:    Bingley, All Saints, Yorkshire, England
Father:    Thomas Foulds
Mother:    Elizabeth Foulds
Abode: Bingley.  Joiner & Cabinet Maker

Died after 1871

John was recorded as a Housekeeper, Deceased in 1887 for Israel's marriage to Hannah. 

No matching GRO records for KEIGHLEY or BRADFORD.  Possibly died at Keithley in 1880 (age 48) or Halifax or Manchester

FOULDS, JOHN        48 
GRO Reference: 1880  M Quarter in KEIGHLEY 
Volume 09A  Page 127

FOULDS, JOHN        61 
GRO Reference: 1885  D Quarter in HALIFAX 
Volume 09A  Page 325

Most likely born in Bingley, as older and younger siblings were born there.

Aged 12 in 1841

Possible match:
Name    Martha Fowlds
Gender    Female
Christening Date    23 Dec 1827
Christening Place    Bierley, Yorkshire, England
Father's Name    Thomas Fowlds
Mother's Name    Rebecca

No death records in Keighley for Martha between 1841 and 1851, so must have married.

Name: Martha Rebecca Foulds
Date of Registration: Jul-Aug-Sep 1850
Registration district: Bradford
Inferred County: Yorkshire West Riding
Volume: 23
Page: 159 

Possibly died as (only half sure):
OVEREND  Martha     Keighley  23 252 

Name: Ann Foulds 
Gender: Female 
Christening Date: 06 Apr 1841 
Christening Place: Bingley, York, England 
Father's Name: Thompson Foulds 
Mother's Name: Elizabeth 
Indexing Project (Batch) Number: I03289-5 
System Origin: England-EASy 
GS Film number: 919131 
Reference ID: p 264 item 2113 

Burial:
Name: Ann Foulds
Parish: Bingley, All Saints
Burial Date: 11 Apr 1841
Burial Age: Infant

Name: William Foulds 
Gender: Male 
Christening Date: 31 Mar 1844 
Christening Place: Bingley, York, England 
Father's Name: Thompson Foulds 
Mother's Name: Elizabeth 
Indexing Project (Batch) Number: I03289-6 
System Origin: England-EASy 
GS Film number: 919131 
Reference ID: p 50 item 393