Multilingualism is a complex phenomenon whose definitions in the literature are not unambiguous or universal. Most often, multilingualism is understood as the knowledge and use of two languages by the same person. There is no agreement about the effect of multilingualism on the child's linguistic and overall development either. Some believe that the multilingual development of children can bring many challenges, but most experts agree that multilingualism brings many positive effects. Of course, multilingualism, like everything else, has its advantages and disadvantages. The main goal of this thesis is to examine what challenges, advantages, disadvantages and difficulties multilingual speakers face. Therefore, research was conducted to answer the questions of whether parents support the development of multilingualism in children, what difficulties multilingual speakers encountered in the context of education and social interactions, and what they consider the advantages and disadvantages of multilingualism. Also, an effort was made to investigate in more detail some of the components of the environmental influence on children's multilingual development. Given that the concept of multilingualism is also linked to culture, the research also wanted to examine how multilingual speakers view the relationship between language and culture and how this affects their identity and self-confidence. The research was conducted using a semi-structured interview method. Nine participants took part in the research, of which six were female and three were male. The respondents were between the ages of twenty-three and thirty, that is, the challenges of children's multilingual development were examined from the perspective of adult speakers. The research results showed that the advantages of multilingualism are numerous and that they dominate certain difficulties and negative experiences. Most of the respondents claim that they have not even encountered any shortcomings. Among the shortcomings identified by the respondents are the mixing of languages and the feeling of less belonging to a group. Also, research has shown that parents and the environment have a great influence on children's multilingual development.