Parents modulate their speech and their actions during infant-directed interactions, and these modulations facilitate infants' language and action learning, respectively. But do these behaviors and their benefits cross these modality boundaries? We investigated mothers' infant-directed speech and actions while they demonstrated the action-effects of 4 novel objects to their 14-month-old infants. Mothers (N = 35) spent the majority of the time either speaking or demonstrating the to-be-learned actions to their infant while hardly talking and acting at the same time. Moreover, mothers' infant-directed speech predicted infants' action learning success beyond the effect of infant-directed actions. Thus, mothers' speech modulations during naturalistic interactions do more than support infants' language learning; they also facilitate infants' action learning, presumably by directing and maintaining infants' attention toward the to-be learned actions. (PsycInfo Database Record (c) 2020 APA, all rights reserved).