Alec Lightwood: I should have guessed you were Jace’s sister. You both have the same artistic talent.

Clary Fairchild (shocked): Jace can draw?

Alec Lightwood (chuckles): Nah. I was just kidding. He can’t draw a straight line.

From the book The Mortal Instruments: City of Bones (Book One) | Written by Cassandra Clare