Noam Chomsky developed a theory called the language acquisition device in 1960.
His theory referred to our brains and abilities as a 'device' that develops when exposed to verbal and non verbal forms of language or stimulating environments.
Chomsky's theory states that all children are born with the ability to develop language but they need to be exposed to it, also known as 'innate'. Often a common misunderstanding is that the exposed language needs to be 'English'.
This is not the case and can be any language, such as German for example. The important concept of the theory is the exposure to a language.