There are various sources of information available to you. One is the LDS (Latter Day Saints - Morman)IGI (Index of Genealogical Information) which lists details of church records (christenings & marriages mainly, held on microfilm) from around the world. One Manx listing, which is the closest to your enquiry, has:
STEPHEN, Thomas son of Thomas STEPHEN & Jane chr 03 Jan 1846, Ramsey, Isle of Man.
This couple is likely to be:
Thomas STEPHEN m Jane COWLE 31 Jul 1842, Maughold, IOM (As Maughold is adjacent to Ramsey)
but it could possibly be:
Thomas STEPHEN m Jane CLARKE 09 Aug 1842, Jurby, IOM
The Maughold MIs (Monumental Inscriptions from Maughold Cemetery) have:
#A45
Sacred to the memory of THOMAS STEPHEN of Ramsey who departed this life the 28th of Decr 1848 aged 33 years also EMILY MARIA, daughter of the above, who died July 4th 1882 aged 33 years. To be with Christ which is far better.
#A44
Sacred to the memory of JOHN JAMES son of THOMAS & JANE STEPHEN who departed this life 22nd of August 1848 aged 14 months, also ELIZA COWLE who departed this life the 7th of November 1859 aged 23 years. Mother, died November 9th 1897 aged 87 years.
#46
Sacred to the memory of RICHARD COWLE of Ramsey who departed this life the 3rd of March 1853 aged 22 years, His end was Peace, also CHRISTIAN STEPHEN who died March 18th 1906 aged 60 years.
There are several possible contenders for this Thos STEPHEN Snr, the closest on the IGI being:
STEPHEN, Thos s/o Patrick STEPHEN & Jane BREW chr 06 Dec 1814, Jurby, IOM
Assuming the "Mother" on the MI is Jane STEPHEN (nee COWLE), then the IGI has:
COWLE, Jane d/o John CAISTEL & Jane COWLE chr 20 Mar 1811, Ramsey, IOM
The mention of "ELIZA COWLE" above would suggest some STEPHEN family link to her parents; William COWLE & Jane CHRISTIAN, Lezayre, IOM.
The IGI is searchable on-line using the IGI "custom search" option at: www.familysearch.com
Ramsey Directories and other useful info is available at Frances Coakley's "Manx Notebook" site at
http://www.ee.surrey.ac.uk/Contrib/manx/index.htm
Other assistance is forthcoming from the "Look-up" service at:
www.isle-of-man.com/interests/genealogy
or from the IOMFHS (Isle of Man Family History Society)members who have transcribed much of the Island's records for further research. They have pages at the above net address.