Gately, the wraith, and the figurants (p. 836)
The wraith says Just to give Gately an idea, he, the wraith, in order to appear as visible and interface with him, Gately, he, the wraith, has been sitting, still as a root, in the chair by Gately’s bedside for the wraith-equivalent of three weeks, which Gately can’t even imagine.
Context
The cost of the visitation, quantified: three subjective wraith-weeks of root-stillness per bedside night. Given the hour-hand rule, this is the book's dead father doing the single most patient thing anyone does in the novel — and it prices out what the E.T.A. phenomena must be costing him.