Kim,
Apparrantly the drum was used by the Wren Boys on St. Stephen's Day. For info on the Wren Boys visit:
Click here

There is a novel by John B. Keane, The Bodhrán Makers, in which the drum and the Wren Dance are central to the narrative. A good read. As for the bodhrán connecting into 'trad' Irish music, word on the street has it that it is a fairly recent (ie. 1900's) phenomenon. Of course, the frame drum has been around forever in many if not most cultures. See Layne Redmond's book, "When the Drummers Were Women" for an exhaustive look at frame drums, women, and goddess culture.

Cheers, Bardford