Born on 25 August 1973 to Lalitha Sivakumar and I. Sivakumar, Nithyasree Mahadevan (previously known as S. Nithyashri) hails from a musical lineage of Carnatic music veterans. Her paternal grandmother, D. K. Pattammal, and her granduncle, D. K. Jayaraman, were renowned Carnatic vocalists while her maternal grandfather was the mridangam virtuoso, Palghat Mani Iyer. A prominent Carnatic music vocalist and playback singer for films, Mahadevan has performed in all major sabhas in India and at prestigious events all over the world. 

She was initiated into music by her mother, who was also her first guru. Consequently, she also underwent training with her grandmother, D. K. Pattammal, and would accompany her in concerts. Her father, an accomplished mridangist himself, was a source of encouragement and inspiration, accompanying her when she performed.