Puerile

puerile \ˈpyu(-ə)r-əl, -ˌī(-ə)l\ adjective: 1. juvenile, 2. childish, silly {puerile remarks}

Etymology: French or Latin; French puéril, from Latin puerilis, from puer boy, child

Sometimes the sound of one word as its uttered suggests another, and so on like a chain: puerile, putrid, puce…