Language is the one area of development that can indicate future success in school. Language development is also important as it can be the earliest sign of a hearing problem or of autism and related problems. A parent is often the first person to have a concern about delayed language. Most doctors will take these concerns seriously. If language delays are investigated early, often the delay can be resolved with early intervention such as speech therapy or correction of hearing loss.
Vocabulary builds so that by eighteen months, most children can say at least five words.
Besides forming sounds and words, language entails gesturing and understanding. Babies should smile interactively by three months and look alert. By nine months a baby should turn to the sound of someone saying his name. By one year, a baby should be pointing at objects of interest and bringing objects to parents and caregivers to show. By eighteen months the child should understand at least fifty words.