For practical reasons, deaf-mute characters do not appear much in narrative ballads; they have, by definition, no dialogue. Deafness in the ballad tends to be either pretended, or the consequence of old age. Although the term "mute" is considered inappropriate nowadays, we have to remember that things were not always so. Certainly my uncle, who was born deaf, would two centuries ago have been functionally mute; not incapable, that is, of articulation (which I believe is a very rare condition) but certainly unable to speak in any intelligible fashion.