This story originally aired Feb. 10, 2007. It was updated July 26, 2007.
Jarrod Davidson was gunned down outside of his Santa Barbara apartment in July 2004, after someone had left what he thought was a gift - a potted plant - at his front door.
As 48 Hours correspondent Maureen Maher reports, Jarrod, 27, was going through a nasty custody battle at the time of his murder.
And while detectives had a theory early on who might be linked to the crime, it was a clue found in that potted plant that would turn this investigation upside down.
Jarrod's cousins, Courtney and Marissa, grew up close to Jarrod and his younger brother, Michael. "When it's the three of us, when it's our family and he's missing…it hurts," says Courtney.
The tragedy has scarred everyone in this tight-knit family.
It was not until he was in college that Jarrod discovered his true passion: chemistry. And it was in chemistry class where he met Kelee Jones.
Kelee says a misprint in the class schedule led her to the "wrong room on the right day. And he was in the right room on the wrong day."
"There was an instant attraction on both ends," she remembers. And she says she fell in love.
About a year after they met, Jarrod and Kelee moved in together. And not long after that, they had some big news to break to both families: "We sat down at a table across from each other and immediately he said, 'Well the reason you're here is because Kelee's pregnant.' And not a heartbeat after that, she said, 'And I'm not having an abortion,'" remembers Jarrod's father Richard.
Kelee says she wasn't trying to get pregnant but that it was a "pleasant surprise." But Jarrod's parents, Richard and Susan, believe she got pregnant intentionally.
Kelee was three months pregnant in January 2000, when she and Jarrod got married. But from the very beginning, the marriage showed signs of trouble.
"I remember once after they were married, me and a friend went to visit them. And she started complaining that he didn't squeeze the toothpaste right. And I said, 'You know what? Me and my boyfriend have the exact same problem. We've decided to buy two separate tubes of toothpaste. You have yours, I'll have mine. Life will go on.' She looked at me like I said the most ridiculous thing in the world. And she went, 'No, he just needs to do it the right way,'" Courtney recalls.
In July of that year, Kelee gave birth to a girl, who they named Malia. "He was so happy. Just so proud and so happy," Courtney remembers.
But those happy feelings didn't last very long. Besides the new baby, Jarrod and Kelee were both still in school and he worked part-time teaching. In fact, they both had jobs, so most of the childcare fell to Kelee's parents, Phil and Mindy Jones.
Jarrod and Kelee's relationship continued to deteriorate. "She started making accusations that he wasn't home enough, that he must be sleeping with his study partner," says Jarrod's mother Susan.
Before Malia's first birthday, Jarrod had moved out and filed for divorce. The court awarded Kelee custody and granted Jarrod visitation; but Kelee made it very difficult for Jarrod to see his own daughter.
"I thought because I had done most of the care giving that it might do them both a little bit of good to take their time and ease into it," says Kelee.
But over time, things only got worse-fighting over Malia went on for the next three years. At times, Jarrod and Kelee both dragged sheriff's deputies into the mess to mediate their visitation disputes.
So when Santa Barbara Detective Greg Sorenson was called to Jarrod's apartment the night of the murder, he was already well aware of the family's domestic problems.
"Instantly, I thought of his ex-wife possibly being involved in this," says Sorenson. "If anybody had the motive to have this carried out, it was her."
But neighbors had reported seeing two suspicious-looking people quickly leaving the apartment complex.