Relations within the subsystem of siblings are an important factor determining social situation of children’s development within the family, their personal peculiarities and social adaptation on the whole. The article presents the empirical study results, which has the purpose of studying manifestation of envy in young men and women, who are the only children in their families and those who have siblings. The hypothesis is based on the supposition that there are differences in the manifestation of envy in young men and women with a different