Megan O'Hara - S1-E6
Continuity mistake: As Christian and Sean are consulting with Megan O'Hara and her husband, you can see a clear shot of the clipboard of her file, and her age states 31 years old. About a month later, Megan dies (Adelle Coffin episode) and after the funeral while Julia and Sean are in an argument concerning his affair with Megan, Julia expresses remorse that Megan died at 36 years old.
Answer: It's a computer graphic.