On her father's side she has French and Northern Irish ancestry. Her mother's side is Jewish, and due to this Lefevre considers herself a cultural Jew. She is bilingual in English and French, but was raised mostly English-speaking. Lefevre also has three sisters.
Her breakout role was as Stacey Hanson on the Canadian supernatural comedy series Big Wolf on Campus. Since then she has become known for her roles in the Twilight films (as Victoria Sutherland), with a number of leading TV roles since around 2009.
Lefevre lives in the US with her husband, chef Chris Crary. In 2016 she gave birth to their child. They adopted another in 2019. Lefevre revealed one of her children was nonbinary in May 2023, and she's been outspoken in support of LGBT+ people due to this.
Selected filmography:
- The Legend of Sleepy Hollow (1999) as Katrina Van Tassle
- Life On A Stick (2005) as Lily (main role)
- What About Brian (2006) as Heather (main role in Season 2)
- The Twilight Saga (2008-9) as Victorianote
- Twilight (2008)
- New Moon (2009)
- Off the Map (2011) as Dr. Ryan Clark (main role)
- A Gifted Man (2011-12) as Dr. Kate Sykora (main role)
- Under the Dome (2013-15) as Julia Shumway (main role)
- Mary Kills People (2018) as Olivia Bloom (main role in Season 2)
- Proven Innocent (2019) as Madeline Scott (main role)
- The Sounds (2020-) as Maggie Cabbott (main role)
