Some years ago a genealogist wrote a book on the Bailey-Brittain family. It is on AncCom. In it he agreed there is no proof of any ancestors of Stephen Bailey. I agree. Some family trees on the internet list a Bailey in St. Olav Parish, London who is claimed to be the father, then they list SB as having been born in Glocestershire, which simply does not compute. One similarity of name does not a link make.
After eight months of work on primary sources: wills, deeds, patents, fiduciary records and surveys, I can say sadly that SB never lived in the Great House. He first lived right across a cove on the Walker land of his wife Mary, then was deeded land to the southwest of the Great House where he lived when he died in 1697. That land stayed in the family until 1778. It also adjoins the Great House. SB's third great grandson Robert bought the Great House property in 1827-28 and built the present house. Prior to that the chain of title to the property was unbroken back to the 1650's patent with no Baileys involved. This has not led me to be very popular here in Kinsale. Stephen Bailey never received a land patent either.
I just tweaked my Bailey site post at http://worldconnect.rootsweb.com/~baileyva
. it is fully documented.