The environment in which child’s language develops is home and the closest surroundings. People who a child the most often interact with have the strongest influence on the development of child’s linguistic system and language competence. By baby language we understand the peculiarities of child’s speech imitated and preserved by adults, especially parents, baby minders and older siblings. Babies language can have positive and negative consequences for developing communication competence of a child. Both from the perspective of linguistics and psychology babies language is a natural way of communication, however, too long use of this language can pose a threat to a child, which leads to impending the development of child’s self-confidence, limiting social contacts through unenabling social interactions different from those existing in a family environment. Another consequence can be child’s speech defects caused by speech distortion, the occurrance of substitutions and elisions, and the reduction of consonants, which leads to disorders in communication competence.