The aim of this thesis is to explore the possibilities of Rusyn language learning, as a Croatian related language, by preschool speakers. Bilingualism and multilingualism is a way of modern life and the most important way of survival of minority languages of stateless nations. In addition, multilingualism is one of the values of the European Union, which is achieved in the family, but also through the education system. This thesis presents the possibilities of Rusyn language learning, as a related Slavic language, by two Croatian language speakers at the age of five. The examinees of the research, who do not attend kindergarten, live in a multilingual environment, in which, among other languages, the Rusyn language is spoken. The aim of the research is to show how language relatedness acts as a stimulating factor on language learning at an early age. Namely, based on the similarity of the words of the Croatian and Rusyn languages, the examined children showed a partial understanding of the Rusyn language. The results suggest that, when it comes to learning foreign languages in the education system, opportunities for learning related languages need to be increased. In the last part of the thesis, Rusyn language learning activities are proposed for preschool children taught by tutors, or digital media at home which is a great innovation in Rusyn language learning. The findings of this paper can be applied to other related languages, as well as to other smaller, minority languages used by the inhabitants of the Republic of Croatia.