The babbling voice of an American baby reflects the timing and intonation patterns of caregivers who speak English. Infants from families speaking Swedish, French, Chinese, or Swahili each babble a unique sound version of their native language. They learn through vocal play and movement and express joy, excitement, pain and disappointment through their voice. They playfully produce all of the sound combinations found in their first language. During this pre-speech period the infant and young child lay the foundation for speech that is clear and melodic.
Children build speech from a series of non-meaningful sound combination patterns.
Some researchers have said that before the age of 9 months babies have produced all the sounds of all languages. As they develop and refine their babbling patterns, they reduce the sound-combination choices to the sound patterns they hear in the languages spoken in their home. New sounds are formed by changing the shape and the size of the oral cavity. Babies develop this coordination as they explore toys in the mouth, and learn to chew and handle more complex foods. Babbling is most frequent and varied between 9 and 15 months when they have developed advanced mouthing skills and the ability to bite and chew.