Domhnall Gleeson has been cast as McGregor, while Margot Robbie, Daisy Ridley and Elizabeth Debicki are providing
unnamed voice roles believed to be members of Peter's family (which, in the books, include his mother and three sisters named Flopsy, Mopsy and Cottontail).
Little has been seen of them in trailers, and some of the
roles remain shrouded in mystery, with each of the Order having separate motion capture body actors and
voice actors - and some of those still going
unnamed.