Final answer:
The period when a child is between 0-6 months old is referred to as the babbling stage. This stage is important for early language and communication development, leading up to more intentional speech later on.
Step-by-step explanation:
The stage when a child is between 0-6 months old is known as the babbling stage. During this period, babies typically start making vocal sounds, smiling, and paying attention to other people. Around 6 months, infants engage in babbling and may also begin to display an understanding of simple words, although their first intentional word usually comes later, between 1 year to 18 months of age. The early months of a child's life are a critical time for language and communication development, and while it is unlikely that they are trying to communicate with their babbling, this stage is essential for their later speech development.