Description:It's the copy of the world's most famous smile. This replica of Leonardo Da Vinci's Mona Lisa temporarily joined her sister in the Louvre museum in Paris. Although it's made by one of Da Vinci's assistants, the copy teaches a great deal about the original, according to the museum. The painting will be on display along with the master's last painting "The Virgin and child with Saint Anne." Louvre paintings curator Vincent Delieuvin spoke about the pieces.(1:47)