[1] Born in Cill na Martra, County Cork, Ó Síocháin was the son of Daniel and Kate Sheehan (née Lynch).
Ó Síocháin was educated locally and, after qualifying as a national school teacher, moved to Dublin in 1935 where he taught for 11 years.
After impressing at club level, Ó Síocháin made his debut on the inter-county scene as a member of the Cork minor team in 1932.
By this stage Ó Síocháin was known nationally as a ballad singer and did some broadcasts for Radió Éireann on such programmes as Ireland is Singing, Round the Fire and Balladmakers' Saturday Night.
Ó Síocháin's grandson, Shane Ryan, was a six-time Leinster medal winner with the Dublin senior team.