In the 1901 census he was living with his parents at 15 Marton St (?), Port Clarence, Co Durham, aged 14, born in Port Clarence, Co Durham.

In 1911 he was living with his mother and her brother Hugh Farrow and young Hugh was a coke filler at a blastfurnace.

Only two marriages of a Hugh Mellon up to c. 1935:

(a) To Agnes Austin:
Surname First name(s) Spouse District Vol  Page
Marriages Mar 1917   (>99%)
AINSLEY Isabella Kettle S. Shields 10a 966
Austin Agnes Mellon S.Shields 10a 966   
Kettle William Ainsley S.Shields 10a  966
Mellon Hugh Austin S.Shields 10a 966

(b) To Mary A Keenan:
Surname First name(s) Spouse District Vol  Page
Marriages Mar 1917   (>99%)
Dew Sarah M Ingram Stockton 10a 118   
Ingram Harry Dew Stockton 10a 118   
Keenan Mary A Mellon Stockton 10a 118   
Mellon Hugh Keenan Stockton 10a 118

The second is in his home area so I’m considering it a possible, now, 2017, confirmed by the family after his daughter Mary’s death in 2017.  Mary is said to have married a Boynton, they had 2 children one of whom was Lawrence.

Mary had a sister Ann (below) who is said to have married a Greenan who was a prisoner of war, by the Japanese, and they had 7 or 9 children.
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The following could well be the children of this last marriage:

Surname First name(s) Mother District Vol  Page
Births Sep 1918   (>99%)
Mellon Francis Keenan Stockton 10a 94   
Births Jun 1921   (>99%)
Mellon Mary Keenan Stockton 10a 229   
Births Mar 1923   (>99%)
Mellon Margaret Keenan Stockton 10a 95   
Births Dec 1924   (>99%)
Mellon Anne Keenan Stockton 10a 155   
Births Sep 1929   (>99%)
Mellon Joachim Keenan Stockton 10a 107
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In 1939 his family was (in part):

1 Queens Terrace , Billingham U.D., Durham, England

FIRST NAME(S) LAST NAME(S) DOB SEX OCCUPATION MARITAL STATUS  SCHEDULE  SCHEDULE SUB NUMBER

Hugh Mellon 09 Feb 1887 Male Electric Crane Driver Overhead Slinger Rigger  Married  46  1
Mary A Mellon 03 Mar 1886 Female Housewife Married  46  2
Francis Mellon 08 Jun 1918 Male Process Worker Plaster Board Manufacturer  Single  46  3
Sorry, this record is officially closed. Check if you can open a closed record.
Hugh Mellon 28 Jan 1927 Male At School Single  46  5
Sorry, this record is officially closed. Check if you can open a closed record.

Ref: RG101/2744G/006/7
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This look alike his death on FreeBMD, the age is right and the district is not far away:

Surname First name(s) Age District Vol  Page
Deaths Dec 1959   (>99%)
MELLON Hugh 72 Durham S.E. 1a 575

In fact this was the only Hugh Mellon death in the country from 1950 to 1990, so I think I’ll go for it.
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A Mary née Mellon died in June 2017 and Kathleen thought Mary was Hughie’s daughter.
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Their marriage index:

Surname First name(s) Spouse District Vol  Page
Marriages Mar 1917   (>99%)
Dew Sarah M Ingram Stockton 10a 118   
Ingram Harry Dew Stockton 10a 118   
Keenan Mary A Mellon Stockton 10a 118   
Mellon Hugh Keenan Stockton 10a 118
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