WATCH: Third murder trial for Dellen Millard gets started

The girlfriend of an aviation executive whose death was initially ruled a suicide told a murder trial her partner was making plans to celebrate her birthday in the days before he died.

Janet Campbell says she was stunned when Wayne Millard was found dead on Nov. 29, 2012, days before her birthday, with a bullet lodged in his brain.

His son, Dellen Millard, has pleaded not guilty to first-degree murder in the death. His judge-alone trial got underway this morning.

Campbell says Wayne Millard was in love with her and she was shocked when Dellen Millard told her his father died ``by his own hand.''

She says she had talked for hours on the phone with Wayne Millard the night before he died and says his aviation business was doing well as it prepared to launch an aircraft maintenance operation.

Campbell says she and Millard made plans to talk the next day but she couldn't get in touch with him, so she emailed his son, who responded with news of his father's death.