Dr. Mark Ben-Aron, a defence witness, told the jury that Sylvester suffered from low self-esteem from an early age.
Ben-Aron said that in his opinion, when Sylvester was called a loser, he acted in an effort to assert himself and out of a feeling of "not wanting to take it anymore," but did not intend to kill the Thornhill woman.
The trial continues on Wednesday.
- ER