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Avenue was the first children's act that Lena Katina joined. It was a Russian pop group formed in 1999, consisting of Katina and Yulia Volkova. The duo rose to fame after winning the Russian national selection for the Junior Eurovision Song Contest 2000, where they represented Russia with the song "Unbreakable." Avenue disbanded in 2003, and Katina went on to form the successful pop duo t.A.T.u. with Volkova.