Mrs. Tittlemouse actually made her debut in 1909 in Potter's The Tale of The Flopsy Bunnies where she rescued the six children of Benjamin and Flopsy Bunny from Mr. McGregor's grasp and was rewarded for her heroism with a quantity of rabbit wool at Christmas.
Potter was an unsentimental naturalist who thought no creature either good or bad, and had no qualms describing earwigs in Mrs. Tittlemouse's passage or woodlice in her pantry.