Clemmons, NC: A Killer Defense: Family Divided When Father Kills Mother

Kirk and Jennifer Turner (Personal Photo) NEW YORK (CBS) When a murder takes place, the justice system rightfully focuses on the participants - victim and killer. But what are the repercussions for the family members - especially a brother and sister faced with the horrible reality of having your father kill your mother?

That was the near-Biblical question facing Wendy and Richie Turner after their father Kirk plunged a knife into the neck of his estranged wife Jennifer.

In an unusual twist for a 48 HOURS | MYSTERY Doctor Kirk Turner, a very successful dentist in Clemmons, N.C., does not dispute that he killed his wife. But he says he did it in self-defense, after Jennifer first attacked him with a seven-foot spear and tried to stab him in the groin.

She missed her mark, Kirk says, but he insists Jennifer stabbed him in the arm and twice in the thigh with that spear. That's when he retaliated with his pocket knife, slicing through her carotid artery and nearly severing her head.

The Turner's two adult children, Wendy and younger brother Richie, immediately found themselves taking sides.

Wendy had already stopped speaking to Kirk after he'd left Jennifer for another woman. Richie had tried to stay neutral during the marital dispute but found himself siding with his father after his mother's death.

It was a radical switch for the two children - Wendy had grown up a daddy's girl while Richie was a mama's boy. His mom often stood up for him when Kirk would spank him for some indiscretion. But now the roles were reversed and both sides were dug in.

Wendy stopped talking with Richie because she says she was afraid he would tell Kirk everything she said. Richie, who admits he never got along well with his sister, felt he was under attack by his sister for standing by their father.

When their father Kirk stood trial for first degree murder, both Wendy and Richie were in the courtroom but sat separately. Wendy sat with her mother' sister while Richie sometimes found himself sitting next to his father's new girlfriend, the woman his mother hated.