Learn English – Pretty Please and Similar Phrases

This is, I think, an instance of ‘baby-talk’ (what linguists call child-directed speech), which is a special dialect adopted by adults in speaking to small children. Although medica is undoubtedly correct in asserting that children employ such terms as “pretty please”, “boo-boo”, “yucky” with each other, I believe they learn them in the first instance from adults.

Some elements of baby-talk—simplified syntax, a deliberately narrowed lexicon, morphological adjustments to mark word and phrase boundaries more clearly—are believed to be of value in providing a child more intelligible models for imitation. But there is a large range of ‘styles’ within this dialect, and many people adopt distinctive (mis)pronunciations and words and phrases which they suppose are characteristic of child speech, as if the child's progressive acquisition of language were not an awe-inspiring and heroic achievement but a species of imbecility to be catered to. At one time it was common in novels to represent the speech of children as baby talk—very like the demeaning representations of African-American or rural or foreign speech which once passed for humor on the stage and in literature.

Baby-talk is also used to pets, and with markedly ironic intent in ordinary speech between adults. And some children, having found that baby talk is regarded as ‘cute’ and endearing, carry some of it terms into adolescence and even adulthood. My impression is that this is less common than it was fifty years ago; I hope I am right.