Thanks for telling me, Emily by Deirdre Madden
Emily's pet shop is no ordinary pet shop and the animals in it are no ordinary animals. When the horrible Mrs Henrietta Fysshe-Pye comes to town and buys pets from Emily, everything goes topsy-turvy. The animals put the world to rights with their cunning and a touch of magic, courtesy of a former magician's rabbit - named, appropriately, Presto!