She is best known for having won the Junior Eurovision Song Contest in 2004. It was in 2002 that she made her first television appearance in the TVE contest "I see, I see." And in 2004, a phone call from his brother to the Euro-junior contest, would change his life forever. María Isabel did her first casting, together with a total of 16,000 children from all over Spain, and was the winner. The award was to represent Spain at the Junior Eurovision Song Contest, of which she was proclaimed the winner with her song "Before Dead Than Simple", with which she was proclaimed winner of the contest organized by the EBU on November 20, 2004.