The son of Wayne Breen, a Covington doctor fatally shot by his wife Kacie last month in an incident still under investigation by the St. Tammany Parish Sheriff’s Office, has filed a wrongful-death suit against his father’s widow.

Sean Breen’s suit was filed Friday in 22nd Judicial District Court. Sean was one of Wayne Breen’s sons with his first wife, Diana. Wayne and Diana Breen had five children together. Kacie Breen, Wayne’s second wife, has one child with him.

Some of the events of March 1 are not in dispute: In the early morning hours, Kacie Breen shot her husband at the couple’s Folsom-area house. She told authorities that she and her husband had been arguing and that she shot him in self-defense. She has not been arrested, but the Sheriff’s Office is still investigating, according to a spokesman.

The suit adds little to the narrative except for one claim: that after being shot, Wayne Breen “lay dying” while Kacie Breen called police. When deputies arrived, the suit says, Breen was pronounced dead.

The suit also questions Kacie Breen’s account of the events of that night, noting that Wayne Breen — a popular and successful obstetrician and gynecologist — had never been arrested for abusing his wife.

Kacie Breen filed for a protective order in 2012, but it had expired by the time of the shooting, Sheriff Jack Strain has said.

The suit also claims that Wayne Breen had been in a car accident a few months before his death, and it implies he wasn’t strong enough to pose a threat of bodily harm to his wife. “As a result of the car accident, Dr. Wayne Breen was rather frail and enfeebled on the date of his death,” the suit reads.

The “sole cause” of his death, according to the suit, was Kacie Breen’s “intentional acts” or negligence.

Sean Breen’s attorney, Rene Frederick, said he had not spoken with the Sheriff’s Office about the case.

“We feel confident that they will do the right thing,” he said. But however the criminal investigation turns out, Frederick said, he believes that Kacie Breen is civilly liable for Wayne Breen’s death.

Breen’s five children with his first wife also have been battling with Kacie Breen over the estate.

Five days after Wayne Breen died and one day before his funeral, Kacie Breen asked to be appointed administrator of his estate, a move that was challenged by the five children of Diana Breen, who moved to have Breen’s son-in-law, Jeff Dunbar, appointed administrator.

On April 21, 22nd Judicial District Judge Scott Gardner appointed Dunbar and Kacie Breen co-administrators. Kacie Breen was given control over property in St. Tammany Parish, Breen’s medical practice and life insurance policies. Dunbar will control any stock, retirement and trust accounts as well as a property in Lafayette that Wayne Breen owned.

Complicating matters, the original of Breen’s will has not been found. Kacie Breen has filed a copy as an exhibit, but a court-appointed lawyer was unable to find an original. Thomas Schneidau, who represents the five children in the succession, has said he does not expect a will to be found and that the matter will proceed “intestate,” or as if no will exists.

Follow Faimon A. Roberts III on Twitter, @faimon.