I would suspect give the dates 1775 and 1841 , they would be in their 80's and statistically beyond the life expectancy :-(

this looks like siblings to Hester....

Year 1789
Month Apr
Day 5
Parents Surname COWBOURN
Child Forename(s) Richard
Father's Forename(s) Thomas
Mother's Forename(s) Elizabeth
Mother's Surname
Place of Residence Redbrook
Occupation
Officiating Minister
Event type Baptism
Memoranda
Notes
Register Reference P227 IN 1/8
Page No 788
Parish/Chapel Newland

THOMAS COWBORN
--------------------------------------------------
Event(s):
Birth:
Christening: 16 JUL 1781 Newland, Gloucester, England
------------------------
Parents:
Father: THOMAS COWBORN
Mother: ELIZABETH
---------------------------------------------------
Messages:
Extracted birth or christening record for the locality listed in the record.
The source records are usually arranged chronologically by the birth or christening date.
----------------------------------------------------------
Source Information:
Batch No.: Dates: Source Call No.: Type: Printout Call No.: Type:
C036202 1560 - 1565 0423272 Film 6911882 Film
C036202 1583 - 1812 0425476 Film NONE
Sheet: 00

Year 1784
Month Oct
Day 24
Parents Surname COUBOURN
Child Forename(s) Ann
Father's Forename(s) Thomas
Mother's Forename(s) Elizabeth
Mother's Surname
Place of Residence Redbrook
Occupation
Officiating Minister
Event type Baptism
Memoranda
Notes
Register Reference P227 IN 1/8
Page No 754
Parish/Chapel Newland

and this may be a sibling or cousin to Hester....

Year 1885
Month Oct
Day 26
Surname COBURN
Forename(s) Thomas
Place of Residence Monmouth
Age at death 85 years
Officiating Minister John Senior
Event Burial
Cause of death
Memoranda
Notes
Register Reference PFC310 1/11
Page No 57
Parish/Chapel Staunton