The subject of this final work is the theoretical foundation of early learning of a second foreign language at an early age and its influence on the development of intercultural sensitivity, the recognition of cultural differences and their acceptance. Learning a foreign language at an early age is conducive to better adoption of that language, easier learning of another foreign language, and developing love for the foreign language and culture it carries within itself. In the first part of this paper, there are presented basic terms, such as what language is and what speech is. It also provides a presentation of the definition of the term mother language, second language and foreign language, which are preconditions for language development and which theories are the result of linguistic research. The second part of the paper indicates how the child learns and adopts the second language and which are the main obstacles. This paper deals especially with speech issues. It is quite logical to ask the question whether speech is something that the child will develop only from himself or is it necessary human environment in which language is spoken? There is no need to think of a particular language but any form of speech. There is known the term bilingualism as the "culprit" for early learning of foreign languages, as well as the influence of children of the same age on encouraging and achieving communication in a foreign language. Playing and socializing with children of the same age and other children is a precious source and inspiration for playing and learning in in a natural environment, to children close and appropriate way, which is especially accomplished in kindergartens. In addition to building their own personality, this has also manifested in children's progress in learning foreign languages.