“All the cool kids are sleeping with stuffed animals these days.”
Mrs. Stinkbottom is a bright green gulon stuffed animal. In Neverseen, she was given to Keefe by Elwin, under Sophie's suggestion, when a memory about Lady Gisela, previously washed, resurfaces. This revelation threatens to break Keefe from guilt. The guilt manifests as recklessness, leading to an ill-conceived plan to sneak away and storm Ravagog by himself, with nothing more than Mrs. Stinkbottom, a melder, and a few cube-shaped gadgets Dex made.
In Lodestar, Keefe leaves Mrs. Stinkbottom behind when he runs away. However, Sophie realizes that she is not in Keefe's room. Later in the same book, she finds Mrs. Stinkbottom in Lord Cassius's room, having leaped there with the starstone found in Cyrah Endal's stall by Caprise Redek. It is assumed that Lord Cassius had been sleeping with it as a way of coping.