Looks like we are related. Sinon's parents were John O'Gorman b. 1765 County Clare and a daughter of Malachy Foley (no name for his wife). They were married in 1764.
John's siblings were: Thomas, died at an early age; 2nd Thomas 1786-1879; Patrick, died a young man in Ireland; Mary, b. 1788; Brigid, b. 1790; Hannah, b. 1792; Honora, b. 1794; and another unnamed daughter.
I have a document that was done in 1966 that gives a history of the O'Gorman family in County Clare Ireland as well as the family crest and about 10 pages of family information. If you would like a copy, send your mailing address to my e-mail - firstname.lastname@example.org