no-one knows for certain - see www.manxnotebook.com/fulltext/pn1925/rnsh.htm (all of Kneen is on my site) where it is thought that it passed to the Sheading via the Abbey's possession of Glen Rushen in Patrick (giving it's name to the Abbey and then to the Castle in the Sheading of Rushen) - I havn't looked to see what George Broderick made of the name - try emailing the Museum as they have it on their shelves (too expensive for mere mortals like me to buy)