Jackett, who comes from a long line of Portuguese fishermen, has been married nearly 30 years. At 52, he has five grown children and is already a grandfather.
He should be enjoying this time of his life. But lately that's been impossible. What happened here on Jan. 6, 2002, changed not only Jackett's life, but the town of Truro as well.
Correspondent Susan Spencer updates a mysterious murder case that was reported on Aug. 5. 2002.
In January 2002, Christa Worthington, a glamorous former fashion writer, was murdered in her home, stabbed in the chest.
Her death was the first homicide in Truro in more than 30 years. Police say she was dead at least 24 hours before they arrived.
They found her two-and- half-year-old daughter, Ava, alone with the body. Spilled cereal revealed that Ava had tried to feed herself after her mother was killed. There were also signs that the door had been forced open.
The grisly murder made headline news across the country. And it has now led to a new book that comes out this week. Writer Maria Flook, who lives in Truro, explores Christa Worthington's life and death in "Invisible Eden: A Story of Love and Murder on Cape Cod."
Flook, who has seen the crime-scene photos, can testify to the brutality of this crime: "It was my introduction to Christa Worthington, to see her half naked body felled on her kitchen floor. In a pool of blood."
Worthington, 46, was a Vassar graduate from a prominent New England family. She had worked as a fashion journalist, writing for Women's Wear Daily, Elle and The New York Times.
"She was a very radiant fashion figure all over Europe," says writer Melik Kaylan, who met Worthington in the '80s. "She was a very glamorous figure."
At just 26, Worthington landed a job in Paris writing for Women's Wear Daily. Among her coups, an interview with fashion heavyweight designer
Yves Saint Laurent.
"She was very interested in the fashion stuff, but she really wanted to make her mark in a more serious area," says Kaylan.
Worthington wanted to write a play, so in 1997, around her 40th birthday, she left the big city for Truro, where her family had spent summers.
However, the quiet she sought in Truro contrasts sharply with the pool
of suspicion swirling around her murder - which has a list of possible
suspects worthy of Agatha Christie.
On the list is a 29-year-old heroin addict and former prostitute, who was allegedly having an affair with Christa's 73-year-old father, a former Massachussetts assistant district attorney.
Worthington told friends that she wanted her father to end his relationship both with the woman and her friends.
Then there's an ex-boyfriend, Tim Arnold, who says he discovered her body when he went to return a flashlight. There are also conflicting reports as to how well they got along.
Just this week, a Boston newspaper reported that Arnold has been told he's a prime suspect in the murder. Arnold, however, isn't talking and his lawyer says his client denies any involvement in Worthington's death.
And finally, there's Tony Jackett, who had an affair with Worthington and fathered her daughter, Ava.
Worthington's friends say Jackett was just a fling. But Flook says she heard from others that Worthington was in love with him. "I was told by a couple of her different friends that she would have married him in an instant, if he'd asked her."
Jackett decided to end the relationship after people began to talk, but
Worthington told him she was pregnant.
"There are many people who accuse Christa Worthington of entrapping Tony so that she could become pregnant," says Flook. "There are other friends of her who swear that it was a total happy surprise when she became pregnant. My feeling is that nobody will ever know."
For almost two years, Jackett managed to keep his affair with Worthington secret. But in December 2000, Christa demanded that Jackett tell his wife about the affair, by then long over, and about their child, Ava.
"I think she became alarmingly aware of the likeness that Ava was taking on," says Jackett. "And she was concerned that Ava would be asking
Finally, Jackett told his wife, Susan, about the affair. And Susan Jackett did something extraordinary. "I have to make up mind if I'm gonna make my marriage work," she says. "It's been too many years and he's a nice man. People make mistakes. He's only human. I don't want this anger in me. I want to make this all work."
Susan Jackett also decided that she wanted a real relationship with her husband's former lover and Ava.
Eventually, the Jacketts got to know Christa, and became very close to Ava.
But Flook says that attitude confused Christa. "I was told that perhaps Christa had hope that Susan would be so angry with Tony that she might leave him," says Flook. "But Susan is a very strong wife."
In January, everything changed when Christa was murdered - and Tony Jackett found himself on the list of possible suspects.
"My father did not kill Christa. And could not harm a fly," says Jackett's son, Beau. Tony, too, claims he's innocent, and he took a lie detector test to prove it.
After Worthington's death, the Jacketts assumed they would raise Ava.
"Where else would she go? Who would love her more than biological family, her father," asks Susan Jackett. "We had already fallen madly in love with her. It was easy to think that we would raise her."
The Jacketts say they thought, for the most part, that Worthington was happy that they were involved with Ava. But others aren't so sure.
"There is no way she wanted Tony to have custody," says Worthington's friend, Kaylan.
In fact, two months before her death, Worthington wrote a will naming longtime friends Amyra and Cliff Chase, not the Jacketts, as Ava's guardians. Ava is now living with the couple in an upscale Boston suburb. But the fight for full custody has become a Jackett family crusade.
Since 48 Hours first reported on this story, the Jacketts have decided to give up the fight for sole custody of Ava. Under the custody agreement, they get to see Ava for two days, every other week.
"I know that I'll always be her father, and I'll have a relationship
with her," says Jackett.
Today, Tony and Susan Jackett still seem comfortable with their decision about Ava - comfortable too, more or less, with each other.
"Our marriage is stronger than ever," says Susan Jackett. "And as odd as
it may sound, I think little Ava has brought us closer together."
Jackett has never been officially cleared in the murder investigation. But he thinks those who know him will know the truth. "Having lived here my entire life, people know what kind of person you are - whether you'd be capable of doing something so heinous."
That affair is detailed in Flook's book, which combines fact and speculation into what the editor describes as "literary non-fiction." It's already caused a firestorm in Truro, but Susan Jackett says she hasn't even read it. "It's all in the past. We know what's true and what isn't."
The author rejects any criticism as to what's true in the book, and what's speculation. For instance, there's a scene that Flook describes between Worthington and her mother, both of whom are dead. There's another scene where Ava sees a mouse when her mother's body is on the floor.
"This is what writers do," says Flook. "They dramatize scenes to create
a 'felt-life,' in fiction and in non-fiction."
But Flook has researched the case carefully and she's sure that Tony Jackett could not have killed Christa. "Tony Jackett, I don't think, could hurt a fly. I cannot say I feel the same about everybody."
Her book, however, speculates on one theory - that a third party witnessed Worthington with a suitor and may have become alarmed, jealous or angry. "I believe that a mistake of passion occurred. And a mistake of passion is a little different from a crime of passion."
District attorney Michael O'Keefe says recently revealed DNA evidence shows that within hours of her death, Christa Worthington had sex - for now, a mystery man.
"It's DNA of an unknown male that's consistent with someone having had sexual relations with the victim," says O'Keefe. "And it's that DNA that we seek to match."
Dozens of people have been tested so far, including Tony Jackett and Tim
Arnold. But so far, there isn't a match.
"One of the possible scenarios, and a likely one, would be that Christa Worthington was murdered by somebody she knew," says O'Keefe.
Investigators insist the case is still active, and that it will be solved.
But for now, mystery still surrounds the murder of Christa Worthington,
whose life was taken on Cape Cod's outer banks -- at Land's End, where
she'd come for peace.