Many languages exhibit constraints on prosodic words, where lexical items must be composed of at least two moras of structure, or a binary foot. Demuth and Fee (1995) proposed that children demonstrate early sensitivity to word-minimality effects, exhibiting a period of vowel lengthening or vowel epenthesis if coda consonants cannot be produced. This paper evaluates this proposal by examining the development of word-final coda consonants in the spontaneous speech of four English-speaking children between the ages of one and two. Although there was no evidence of vowel lengthening, coda consonants were more accurately produced in monosyllabic target words with monomoriac vowels, suggesting earlier use of coda consonants in contexts where they can be prosodified as part of a bimoraic foot. One child also showed extensive use of vowel epenthesis and coda consonant aspiration concurrent with the production of codas. However, we show that this was due to the articulatory challenges of producing complex syllable structures rather than an attempt to produce well-formed minimal words. These results suggest that learners of English may exhibit an early awareness of moraic structure at the level of the syllable, but that language-specific constraints regarding word-minimality may be acquired later than originally thought.