for more information:
Sosa, A. V., (2016). Association of the type of toy used during play with quantity and quality of parent-infant communication. JAMA Pediatrics, 170, 132-137.
Grammar, Phonology, vocabulary, and pragmatics continue to grow during the preschool and school age years:
Children become able to express themselves increasingly complex ways (requesting predicting, reasoning, etc.)
Speech sound development improves and intelligibility becomes clearer
vocabulary use increases and the understanding of the relationship between words increases
Grammatical morphological function improves
... most babies are aware of their mother's voice before they are born.
...crying is reflexive and tells us an infant's early needs - for example, when they are tired, hungry or are in pain. Around 1 month, infants will begin to coo and goo!
...around 7-10 months, infants begin to replace their "mushy" babbling sounds with clearer sounding babbling. They will begin to saying things like ba-ba-ba-ba and ma-ma-ma-ma.
...around 11-12 months, infants will begin to babble in "gibberish" and they will sound more like they are talking!!!
At the same time, they are crawling and may even begin to walk.
Also during this time, they become intentional in their communication. This means that for the very first time, they really understand that when they babble they are communicating. They will likely begin to use gestures like pointing or waving bye-bye at this time, too.
...babies usually learn their first words between 12 and 15 months.
...babies usually learn their first 50 words between 12 and 24 months.
...babies have a sudden interest in words, also known as a vocabulary explosion, around 18 months.
...babies usually begin combining 2 words together sometime after the vocabulary explosion (around 24 months).
...by 24 months many toddlers have 200-300 words in their expressive vocabularies!