Friday marked the first full day of testimony in the trial of a Bay Shore man accused of fatally stabbing his wife in front of their child.

Just over two years ago, 39-year-old Regina MacFarlane was found dead inside her home. Prosecutors say her husband, Elden MacFarlane, stabbed her to death as their 10-year-old daughter looked on. Prosecutors showed evidence from inside the home during Friday?s testimony, including blood-spattered walls and the victim?s lifeless body.

During opening arguments Thursday, the defense told jurors that Elden, a military veteran, was not responsible for the stabbing because he was suffering from psychological illnesses at the time.

?It was brought on by hallucinations, delusions and mental illness in the family. It became fully manifested several months before the incident,? said defense attorney William Ferris.

Prosecutors have a chilling 911 tape of the entire stabbing after someone picked up the handset, dialed for help and left it on a chair with an operator listening. That tape, along with the testimony of MacFarlane?s daughter, will be very crucial to the prosecution. The jury is expected to hear the 911 tape sometime next week.