Sunny Baudelaire is an "Infant", a word which here means: "A small child whom is so young they can only speak in a series of indistinguishable shreiks and noises which most people find difficult, if not impossible, to understand."
"Indistinguishable" Is a frighteningly long word whose definition I will not say, for I fear I have found myself, in this moment in an antique celebrity chandeleir museum clicking away on my typewriter, too overwhelmed with the utter sadness and despair of young Sunny's life, as written in these books... That I cannot bring myself to write the meaning of such an obscure and lengthy word.

Sunny Baudelaire is one of the main characters, and though her lines are often short, they are common.