Bulgarian folk dances are intimately related to the music of Bulgaria. This distinctive feature of Balkan folk music is the asymmetrical meter, built up around various combinations of 'quick' and 'slow' beats. The music, in Western musical notation, is often described using compound meter notation, where the notational meter accents, i.e., the heard beats, can be of different lengths, usually 1, 2, 3, or 4.
This clip is called "Dear Mama, dance with me!" . Children and their mothers danced together. The celebration was dedicated to the spring holidays.