E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Little pitchers have long ears. Little folk or children hear what is said when you little think it. The ear of a pitcher is the handle, made in the shape of a mans ear. The handle of a cream-ewer and of other small jugs is quite out of proportion to the size of the vessel, compared with the handles of large jars.