Last year, Nina was known as the sweet Mia on Degrassi: The Next Generation, but now she's a household name with a starring role as Elena on the hit CW series The Vampire Diaries! Looks like this year is going to be a good one for the actress who celebrates her 21st bday today! Happy Birthday, Nina!

Fun Facts About Nina:
-They may be super hot, but Nina spilled to J-14 that she sees her vampire costars as "big brothers."
-The actress told J-14 that one of her best friends from her time on Degrassi is Paula Brancati who plays Jane! They still keep in touch.
-Tearjerker Stepmom is one of her favorite movies ever! She told J-14 that the song "Ain't No Mountain High Enough" by Marvin Gaye is on her top playlist because of it.

Leave your birthday messages for Nina below!

Photo: Courtesy of the CW