Duet Mania (Bulgarian: Дует Мания) is a Bulgarian pop duet formed in Sofia, Bulgaria in 1999 and consisting of two sisters: Daniela Atanasova and Julia Dimitrova. Duet Mania members began their musical endeavors in their pre-teens in their home town Dimitrovgrad, Bulgaria, as members of a children choir called "Happy Childhood" and as lead vocalists of a band called "Sparkles". After years of performing underground they were signed to "PolySound" as Duet Mania.In 1999 they released their first best-selling album called It's Not True, which contained the number one singles "The World is For Two", "Cricket's Song", "It's Not True", "I Don't Want, I Can't".The album went on to become a critical and commercial success, with estimated sales of more than 50 thousand. They are the most successful