Our study aimed to examine longitudinally early development of gestures, object-actions (short for object-related-actions), word comprehension, and word production and their reciprocal relationships in typically developing infants. Twenty-two monolingual Italian infants were followed monthly from 0;10 up to 1;5 with the Italian short form of MacArthur-Bates CDI — Gestures and Words. Results showed that gestures, object-actions, and word comprehension increased significantly from 0;10 to 1;5, with an earlier development of gestures with respect to object-actions, while production started to increase significantly from 1;0. A developmental advantage of girls with respect to boys was found in gestures, object-actions and word comprehension. Relationships were evident between object-actions and word comprehension at all ages, between gestures and both word comprehension and word production in their phase of emergence, and between word comprehension and word production at the emergence of word production.These findings suggest that gestures support the emergence of verbal abilities, while object-actions contribute to the construction of the representation of meanings.