Infant-directed speech (IDS) is the register commonly used in infant-adult interactions in many linguistic communities, and presents a number of special lexical, syntactic and prosodic particularities when compared to adult speech, such as words with syllable reduplication, high question rate and exaggerated prosody. In this study, we focus on interrogatives and their prosodic properties as the object of investigation. Data analysis of interactions of ten Brazilian Portuguese-acquiring infants aged 4 to 12 months and their caregivers, revealed that questions corresponded to 33% of the total utterances produced and are emphasized mainly by marked pitch (raised pitch range and expanded pitch span), as well as increased duration. Moreover, the pitch contours of Wh and Yes/No questions followed their respective patterns observed in adult speech. These results are compatible with those found in the literature and indicate that, in general, the IDS used in Brazilian Portuguese has similar characteristics to this register in other languages.