In 1996, Vega starred as young Jo Harding in "Twister". She guest-starred in numerous television shows and films, including "ER", "Follow the Stars Home", "Ghost Whisperer", and "The Bernie Mac Show". She became known worldwide in 2001 for her role as "Carmen Cortez" in "Spy Kids". The first "Spy Kids" film was a huge success, and subsequently two sequels, ' and ' were filmed. During the shooting of the three films, she performed most of her own stunts. In 2011, Vega appeared in the sequel, "", as a grown Carmen Cortez.