RONAN/ROWA(E)N/RONA(Y)NE/ROUGHAN - NAME VARIENT'S

[JPRonan]

Greetings to you all,
Is anybody able to confirm that ROUGHAN is a name varient of RONAN (and it's varient's above)?, or have any suggestions as to where to look next?
I do have a record that suggest this is the case (see below). Here is the info I have so far collected, they seem to move over the Shannon and back again.....

My Dad, Christopher RONAN (RONANE on Marr. Cert), was born in Ennis in 1928. He had several sibling's and they lived at Ballycar, Newmarket-on- Fergus. He is buried in Tomfinlough.

Their parent's were James RONAN and Josephine Cadwell who lived, and married, in Quinn in 1924. Josephine originally was from Dublin.
James RONAN was born 25.04.1889 and Baptised in Limerick, Parish of St. John. He appears on the 1901 and 1911 Census, living with his maternal Grandmother, Sarah Foley, in Limerick. (His Mother, Mary Moloney, died in 1891).

James had older sibling's - John ROWAN b.16.08.1885, Sarah ROWAN b.08.11.1883 and Charles ROWAN b.04.05.1882.
Their Parent's were James ROWAN and MARY MOLONEY who married in Limerick 26.02.1881 (Dist. No.3, The RC Cathedral) James is ROWEN on this Cert.
This James was Married 3 times, having being widowed twice. He appears on the 1901 and 1911 Census with his 3rd wife, Catherine Sexton ( Marr. 13.11.1891, St Michael's Lim.) On the 1901 Census James is listed as being from CLARE. They live in (Back)Clare St. Limerick.

I am struggling to find any birth for this James...
JAMES ROWEN'S 1st Marriage was to Margaret Sheahan, also at St. Michael's, Lim. on 09.01.1887. At that time he lived in Ellen St. and his Father is CHARLES ROWEN, a Herdsman. Margaret died 27/12/1880.
JAMES ROWEN'S 2nd Marr. to MARY MOLONEY in 1881 ( see above)- at that time he lived in New Rd. Lim. (This is where my line were born) His father is CHARLES ROWEN, a Herdsman.
JAMES ROWAN's 3rd Marr. to Catherine Sexton in 1891 (see above) at that time he lived on Clare St. Lim., they had several chidren.
JAMES died in August 1924, still living at Bk Clare St.
This James would be born c. 1855??
I have a CIVIL Marr. Rec. of ANNE ROWAN, father is CHARLES ROWAN, to a RICHARD RONAYNE, 05.06.1875, at St. MIchaels, Lim.
On the CHURCH Marr. Rec.the details/spellings are the same.
It is their children where the ROUGHAN spelling is introduced.
On familysearch.org is MARY ELLEN RONAYNE, b. 27.05.1876, parents, R. RONAYNE and ANNE RONAYNE/ROUGHAN. Same on her Civil Birth Rec. (roots Ireland) on her Bap.Cert (roots Ireland) her Parent's are R. RONAN and ANNE ROWEN
ANNE MARGARET ROWAN b.26.06.1878 - parent's R. RONAN and ANNE ROUGHAN/RONAN.....It seems the civil reg. has ANNE as ROUGHAN and the Church reg. as ROWEN.
I cannot confirm that ANNE, daughter of CHARLES is a sister to my JAMES, son of CHARLES. I cannot find Baptism records for them
in Limerick or a Marriage for CHARLES.
I was always told my Family were from CLARE and it may be that CHARLES is. His son James is listed as being from Clare on the 1901 Census although it states Lim. City on the 1911 Census.
As I look at Clare Record's I see there are far more record's for ROUGHAN around the 1850's than the other name varient's.
So...... back to my query, is it safe to assume I am now looking for CHARLES ROUGHAN?

I have recently seen, on this site, the Parish Rec. for O'Callalaghan's Mills. There is a Baptism of a JAMES ROUGHAN 16/19th Jan. 1839. His parent's are CHARLES ROUGHAN and MARY MEEHAN....maybe this is my JAMES, the date seems to early though....
has anybody noticed a CHARLES in their records/searches?
I would appreciate any help,
Best wishes to all,
Josie