(Painesville) - The murder trial of a Willoughby Hills man continued in Lake County Common Pleas Court.

Forty-three year old Kevin Knoefel facing sex charges related to his foster daughter, and complicity to commit aggravated murder in the killing of his 41 year old wife Lisa.

Investigators claim Knoefel convinced his 19 year old foster daughter Sabrina Zunich to stab Lisa to death.

Prosecutors believe Knoefel had an illicit affair with his foster daughter starting when she was 17 and wanted wife Lisa out of the way.

On the witness stand Wednesday was David Strunk, a family friend of the Knoefels and a former co-worker of Kevin Knoefel.

Strunk testified that on a camping trip with the Knoefels, Kevin told him that wife Lisa suspected he was having an affair with foster daughter Sabrina.

David Strunk

Strunk said Kevin even told him that Sabrina had purchased comfortable underwear for him to wear.

After Lisa was later found murdered, Strunk testified that Kevin asked him to check into a $250,000 life insurance policy he had on wife Lisa.

When Sabrina was taken into custody by Willoughby Hills Police, Strunk said Kevin tried to visit her, and became upset when he wasn't allowed to. Strunk said he did not understand why Kevin would want to have any contact with the person suspected of killing his wife.

Strunk said he and Kevin visited the blood splattered bedroom where Lisa was killed, and that Kevin showed little emotion.

Strunk testified that he asked Kevin if he had an inappropriate relationship with Sabrina. Strunk claimed Kevin abruptly changed the subject.

Earlier this week, the jury visited the scene of the crime, where Lisa Knoefel was found stabbed to death. Prosecutors claim Kevin was having an affair with Sabrina who is charged with murder. Kevin contends his daughter acted alone.

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(Photos by Ken Robinson/WTAM)