ALL SHE COULD utter was his name - "Giocondo" - but even that proved too painful for the frail, elderly woman, and she retreated back into the dark hallway of her South Philly rowhouse.

"Giocondo. Giocondo," Lida Navek repeated softly with a faint Italian accent. "His name was Giocondo. Giocondo."

Dr. Giocondo "Joe" Navek, 39, was the elder of Lida Navek's two boys, the pride of a South Philadelphia family who became a decorated soldier, a paramedic, a doctor and a father, then suddenly, a dead double-murderer.

To add to Lida Navek's anguish, on April 5, her troubled, younger son, Bruno, 36, was arrested for allegedly raping an underage girl.

"We still can't believe this is all happening. He wasn't that type of person. He was so well-put-together," Bruno's wife, Audrey, said of her brother-in-law Joe, after getting off the phone with her husband in prison last week.

Former colleagues and superiors would argue that Joe Navek wasn't put together so well, but none imagined he'd unravel into the rage that killed Dr. Payman Houshmandpour, a former colleague of his in South Jersey, and Shawna Givens, a married mother of three whom Navek wooed while he was working as a doctor at a North Carolina Army base.

"He was so clearly troubled; it wasn't difficult to see that," said an instructor of Navek's at Virtua Hospital's Family Medicine Residency Program, in Voorhees.

Joe Navek and his little brother split their youth between their mother's home on Clarion Street near Federal and a relative's home on 17th Street between Shunk and Porter. Navek's mother worked at a small newsstand at Broad and Ellsworth for decades. Her husband died when they were young, Audrey Navek said.

Family members on 17th Street repeatedly declined to comment, and all one neighbor could remember was how protective Joe Navek was of his gleaming Mercedes.

"I put my hand on it once to get my balance and he screamed, 'Don't touch that car! That car cost $175,000!' " said the neighbor who asked not to be identified.

Bruno Navek, according to his Facebook profile, attended South Philadelphia High School. The brothers took different paths in life, with Bruno having been arrested dozens of times, police said, mostly for drug offenses. Bruno is due in court Wednesday for a preliminary hearing on charges including rape and supplying alcohol to a minor for an incident that allegedly happened in his mother's home last summer. Bruno told police he worked as a barber in West Philly.

Audrey Navek said her husband's arrest was a "misunderstanding," and Bruno declined to comment about his brother when she passed the phone to this reporter.

Joe Navek, according to his sister-in-law, had never been in trouble with the law and joined the Army when he was a teenager. Army officials said that Joe Navek enlisted in 1990 and was stationed as a Hawk-missile crew member in Germany and Fort Bliss, Texas. Navek completed his service with the Army Reserve in 1997 and was discharged as a corporal.

Navek earned a marksmanship badge and other awards.

In 1996, Navek graduated from the Philadelphia Fire Academy's 14th Medic class and worked until 2000, mostly at Medic 13 at 19th and Oxford streets. Former co-workers told the Inquirer that he was highly competitive and erratic.

By June 2002, he was describing himself in online discussion boards as a second-year medical student dedicated to his beloved Mercedes. Navek often wrote long posts, detailing every modification he made to his 2001 CLK 55. Sometimes he got in arguments over the aesthetics of certain brakes.

Navek got his medical degree from St. George's University in Grenada. He later wound up in the residency program at Virtua along with Dr. Shohreh Sameni, Navek's former fiancée and the mother of his son, and Houshmandpour, the man he shot to death on April 11.

The former Virtua instructor, a doctor who spoke on the condition of anonymity, said it was never clear whether Navek was a skilled physician because his personality problems clouded everything.

"He definitely had problems with authority, particularly women. He had extreme difficulty taking constructive, helpful directions, or just plain feedback," the doctor said. "He would react in a very, very aggressive manner."

Another Virtua employee, who also spoke on condition of anonymity, said Navek was a "meathead" who gave women the "creeps."

Navek was dismissed from the residency program about 18 months ago, hospital officials said, and apparently blamed it on Houshmandpour, a married father of a young daughter. Houshmandpour had befriended Navek, the former instructor said, and had tried to help him after most had written him off.

"There's only one person to blame for what happened, and it's Joe," the instructor said.

According to the Army, Navek re-enlisted in the Reserve as a captain in 2009 and had been stationed at Womack Army Medical Center, at Fort Bragg, N.C., since September. That's where he met Shawna Givens, a medical-support assistant. The two began dating while he split his time between there and Williamstown, Gloucester County, where he lived with Sameni and his child.

"Shawna liked the attention he gave her," said Kris Delgado, a friend of Givens' from Fayetteville, N.C.

But Delgado and other friends said they saw signs that Navek was unstable: He cried for no clear reason, picked fights and sometimes would drink through the night, long after Shawna went to bed.

Sameni eventually found out about Givens and left with their son, the Associated Press reported. The Camden County Prosecutor's Office said Sameni filed a police report in Gloucester County on March 22, claiming Navek had threatened her and fired shots in the basement of their Williamstown home in February.

When Navek brought Givens home to Philadelphia, he introduced her as his girlfriend. Audrey Navek said they seemed crazy about one another when the three went to Jon's Bar & Grille on South Street on Good Friday.

"They wasn't fighting or nothing," Audrey Navek said. "We all had a good time."

On Easter, Joe Navek and Givens stopped at his home in Williamstown. Neighbors said the tall, thin blonde watched Navek cut the lawn, and nothing seemed out of the ordinary.

But two days later, he returned to Philadelphia alone and borrowed a family member's Nissan.

The next morning, April 11, he was waiting for Houshmandpour outside his apartment in Voorhees and blasted his Audi with bullets when he pulled out of his parking spot. Houshmandpour died at the scene. Navek shot himself in the head when Voorhees police pulled him over nearby.

Meanwhile, in Fayetteville, investigators went to Givens' home that same day after she didn't show up for work. They discovered her body about 12:30 p.m., and authorities confirmed last week that she had been killed with the same gun used to kill Houshmandpour.

Houshmandpour, an Iranian native, was also from North Carolina, and his services were held there Saturday. Givens' funeral was held there last week, on just the kind of hot and sunny day Delgado said she loved.

"It was beautiful," Delgado said.

Navek's body was still in the morgue last week as Audrey Navek scrambled to see whether Bruno could be released, even briefly, to say goodbye.

"Joe loved his little brother," she said. "He needs to be able to see him go."

Bruno didn't get out, but an employee at Baldi Funeral Home in South Philly said a "fair amount" of people did show up to say goodbye to Joe Navek on Friday.

"It was a nice crowd," the employee said. "He was a local guy from the neighborhood."

Contact Jason Nark at 215-854-5916 or narkj@phillynews.com, or follow on Twitter @JasonNark.