DoB from age 77 at death in 1891.

Source: Death register in General Registry Office.  Died of "wound of spine" after 5 days in Letterloan.  Present at Death was his son, also John McKeown.

77 at death in 1899

Name    REBECCA MCKEOWN
Year of Death    1899
Group Registration ID    4343670
SR District/Reg Area    Coleraine
Deceased Age at Death    77
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Widower of Letterloan, daughter, Mary McKeown, also of Letterloan, PAD.

Date of Birth source: 1901 census - and also his death certificate which gives his age as 60 in 1902. 

 Date of Death from General Registry Office, Belfast - died of heart disease after 1 month's illness in Balteagh.  His wife Ellen McKeown was Present at Death, she also from Balteagh.

Source:  Barbara Braswell, using the International Genealogical Index: "MARGARET MCKEOWN Female   Family Event(s): Birth:  About 1845   , , Ireland Christening: Death:  16 JAN 1874   Croghan, Articlave, Londonderry, Ireland Burial: Marriages: Spouse:  JOHN DOEY  Family Marriage:  07 JUN 1869   Reg Office, Coleraine, Londonderry, Ireland" NB:  Margaret died in Croaghan, which is the address which Martha McKeown nee Dowey gave as the Dowey home on her second application to the Pensions authorities.  In other words, Margaret was probably married to a Dowey who still lived in or near the family home. 

Source:  Barbara Braswell, using the IGI: "MARGARET MCKEOWN Female   Family Event(s): Birth:  About 1845   , , Ireland Christening: Death:  16 JAN 1874   Croghan, Articlave, Londonderry, Ireland Burial: Marriages: Spouse:  JOHN DOEY  Family Marriage:  07 JUN 1869   Reg Office, Coleraine, Londonderry, Ireland" NB:  Margaret died in Croaghan, which is the address which Martha McKeown nee Dowey gave as the Dowey home on her second application to the Pensions authorities.  In other words, Margaret was probably married to a Dowey who still lived in or near the family home. 

50 at death in 1898

Dead by 1901 census - wife gives herself as widow.  If I had this man's Date of Death, I would have his age, which would tell me if the McKeown girls who married the Leighton boys, could be his daughters.  I suspect that he is considerably older than his wife, because of his father's age, and he could therefore easily be their father.

Name    JOHN MC KEOWN
Year of Death    1898
Group Registration ID    4300449
SR District/Reg Area    Coleraine
Deceased Age at Death    50
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Married labourer of Letterloan, wife, Martha, of Letterloan, PAD

Date of Birth = age given as 45 in 1901 census.

Name    MARY MCKEOWN
Year of Death    1906
Group Registration ID    3633494
SR District/Reg Area    Coleraine
Deceased Age at Death    48
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Spinster of Letterloan, nephew, Thomas McKeown, also of Ltterloan, PAD.

38 in 1901