Date of Birth taken from marriage entry in 2nd Dunboe Presbyterian Church records, confirmed by 1901 census.  Barbara Braswell has now also found the birth of a Samuel Steen Claments to Samuel Claments and Jane Finlay in 1865 registered in Articlave in the International Genealogical Index at the Family History Library site which claims to be a Civil Records.

Name Samuel Steen Claments
Gender Male
Birth date 04 Oct 1865
Birth place 0446,ARTICLAVE,LONDONDERRY,IRELAND
Father name Samuel Claments
Mother name Jane Finley
Batch number C70126-7
Record group Ireland-ODM
Film number 101115 

Civil Birth Record
Name:    Samuel Steen Clamants    Date of Birth:    10-Oct-1865
         Registration Date:    1-Jan-0
Address:    Ballinreese    Parish/District:    ARTICLAVE
Gender:    Male    County    Co. Derry
Denomination:    Registrar District
Father:    Samuel Clamants    Mother:    Jane Finley
Occupation:    Labourer    
Sponsor 1 /
Informant 1:    Samuel Claments

I now have a copy of his birth cert from GRONI online and he is called Samuel Steen, born 4th October 1865, son of Samuel Clamants, labourer, and Jane Clamants fly Finley, born in Ballinrees, Dunboe, father from Ballinreese and the informant.

There is a John Steen living in Ballinrees in the GV but no McClementses.

Death register entry in General Registry Office shows he died of "Pulmonary TB 12 years", he was a labourer, died in Ardvarness and Sissie McClements, daughter was the informant.

After her death, I received some of Aunt Sadie's photographs and one was of a gravestone with this written on the back:
"Mum's
Mum and Dad
Englishtown
Cemetary
Near Coleraine"
The stone says:
"Erected
In Memory of
Samuel McClements
Ballywilliam
Who dies September 15th 1925
Aged 58 years
Also his wife
Annabella McClements
Who died June 20th 1925
Aged 63 years"
Ballywilliam is just south of Ardvarness

I visited this grave with Susan Schiller and the wording has completely decayed so it is lucky Lynn Moulin sent me the photograph from Aunt Sadie's collection which shows exactly what it said.

Date of Birth source: Civil Registration birth entry in General Registry Office, Belfast.

Ireland, Civil Registration Births Index, 1864-1958 about Annabella M'Keown
Name:    Annabella M'Keown
Date of Registration:    1864
Registration district:    Coleraine
Birth Country:    Ireland
Volume:    6
Page:    471
FHL Film Number:    101041

Ireland, Births and Baptisms, 1620-1911 about Annabella Mckeown
Name:    Annabella Mckeown
Gender:    Female
Birth Date:    17 Mar 1864
Birth Place:    Articlave, Londonderry, Ireland
Father's Name:    James Mckeown
Mother's Name:    Ellen Gibson
FHL Film Number:    101085

Civil Birth Record
Name:    Annabella Mckeown    Date of Birth:    17-Mar-1864
         Registration Date:    
Address:    Letterloan    Parish/District:    ARTICLAVE
Gender:    Female    County    Co. Derry
Denomination:    Registrar District
Father:    James Mckeown    Mother:    Ellen Gibson
Occupation:    Weaver        
Sponsor 1 /
Informant 1:    Ellen Mckeown
Sponsor 2 /
Informant 2:    
Notes:

Death certificate shows she died of "Cardiac Failure Suddenly", and "of the labouring classes".  She resided in Ardvarness when she died.  John McClements, her son, of Ardvarness, was the informant.

After her death, I received some of Aunt Sadie's photographs and one was of a gravestone with this written on the back:
"Mum's
Mum and Dad
Englishtown
Cemetary
Near Coleraine"
The stone says:
"Erected
In Memory of
Samuel McClements
Ballywilliam
Who dies September 15th 1925
Aged 58 years
Also his wife
Annabella McClements
Who died June 20th 1925
Aged 63 years"
Ballywilliam is to the south of Ardvarness.

Baptised in 2nd Dunboe, confirmed by 1901 census.

Church Baptism Record
Name:    Ellen McClamont    Date of Birth:    10-Sep-1886
         Date of Baptism:    01-Nov-1886
Address:        Parish/District:    SECOND DUNBOE
Gender:    Female    County    Co. Derry
Denomination:    Presbyterian
Father:    Samuel McClamont    Mother:    Anna Bella McKeown
Occupation:        
Sponsor 1 /
Informant 1:        Sponsor 2 /
Informant 2:    
Notes:
REV. J. S. KEERS.

I need to find her birth certificate to see if she was born in Ballystrone prior to the family's move in 1897 to Lower Balteagh.  In fact, it would be useful to have all of her siblings' birth entries in order to track the family's movements at this time.

Church Baptism Record
Name:    Mary Jane McClamont    Date of Birth:    26-Apr-1888
         Date of Baptism:    29-Oct-1888
Address:        Parish/District:    SECOND DUNBOE
Gender:    Female    County    Co. Derry
Denomination:    Presbyterian
Father:    Samuel McClamont    Mother:    Anne Bella McKeown
Occupation:        
Sponsor 1 /
Informant 1:        Sponsor 2 /
Informant 2:    
Notes:
REV. J. S. KEERS.

Buried in Second Garvagh Presbyterian Church. Bap in 2 Dunboe, confirmed by 1901 census.

Baptised in 2nd Dunboe, confirmed by 1901 census.

Church Baptism Record
Name:    James McClamont    Date of Birth:    09-Sep-1890
         Date of Baptism:    19-Mar-1891
Address:        Parish/District:    SECOND DUNBOE
Gender:    Male    County    Co. Derry
Denomination:    Presbyterian
Father:    Samuel McClamont    Mother:    Anna Bella McClamont
Occupation:        
Sponsor 1 /
Informant 1:        Sponsor 2 /
Informant 2:

Baptised in 2nd Dunboe, confirmed by 1901 census.

Church Baptism Record
Name:    Samuel McClamont    Date of Birth:    20-Mar-1893
         Date of Baptism:    03-Sep-1893
Address:        Parish/District:    SECOND DUNBOE
Gender:    Male    County    Co. Derry
Denomination:    Presbyterian
Father:    Samuel McClamont    Mother:    Anna Bella McClamont
Occupation:        
Sponsor 1 /
Informant 1:        Sponsor 2 /
Informant 2:

Baptised in 2nd Dunboe, confirmed by 1901 census.

Church Baptism Record
Name:    Martha McClamont    Date of Birth:    26-Mar-1895
         Date of Baptism:    29-Apr-1895
Address:        Parish/District:    SECOND DUNBOE
Gender:    Female    County    Co. Derry
Denomination:    Presbyterian
Father:    Samuel McClamont    Mother:    Anna Bella McClamont
Occupation:        
Sponsor 1 /
Informant 1:        Sponsor 2 /
Informant 2:    
Notes:
REV.J.S.KEERS.

No baptism recorded in 2nd Dunboe - Date of Birth from 1901 census.

Baptised in 2nd Dunboe, confirmed by 1901 census.

Church Baptism Record
Name:    Anna Bella McClamont    Date of Birth:    02-Oct-1899
         Date of Baptism:    11-Mar-1900
Address:        Parish/District:    SECOND DUNBOE
Gender:    Female    County    Co. Derry
Denomination:    Presbyterian
Father:    Samuel McClamont    Mother:    Anna Bella McClamont
Occupation:        
Sponsor 1 /
Informant 1:        Sponsor 2 /
Informant 2:    
Notes:
REV. J. S. KEERS.

Probably died between 1901 and 1911 as she is missing from 1911 census and her mother is recorded as having one deceased child.

Baptised in 2nd Dunboe.

Church Baptism Record
Name:    David McClamont    Date of Birth:    08-Apr-1901
         Date of Baptism:    05-Feb-1902
Address:        Parish/District:    SECOND DUNBOE
Gender:    Male    County    Co. Derry
Denomination:    Presbyterian
Father:    Samuel McClamont    Mother:    Anna Bella
Occupation:        
Sponsor 1 /
Informant 1:        Sponsor 2 /
Informant 2:    
Notes:
REV. J. S. KEERS.

Baptised in 2nd Dunboe.