1999: Colby Marian Chandler was born on Adam Chandler and Liza Colby’s romantic getaway. Colby symbolized a positive turning point in the lives of all the Chandlers. She brought together Liza and her estranged mother, Marian Colby Chandler. Adam and Liza decided to make another go at marriage. But Colby’s conception was still a veil of mystery. Liza believed Jake Martin to be the sperm donor. In reality, Adam had switched his sperm for Jake’s.
Jake had always disapproved of Adam’s parenting skills. When Jake found out Adam and Liza were going to marry again, Jake sued for custody of Colby.

2000: After it seemed like Jake was going to win full custody of Colby, Liza revealed in open the court the truth about Colby’s paternity. The newly divorced Adam and Liza were forced to share custody. They had divorced over Adam’s deception. The news crushed Jake and left town to join Doctors without Borders.

2001: Liza and Adam remarried. They had to marry in Chandler mansion because Adam was under house arrest for the murder of Arlene Vaughan, Hayley Santos' mother.

2002: Liza became very protective of Colby, even alleging that her older brother JR Chandler had tried to hurt her. Liza’s strange behavior was explained by a brain tumor. After an operation, Liza suffered some amnesia. Adam attempted to gaslight Liza into thinking she was going crazy.
Colby became very attached to her aunt, Mia Saunders. Adam saw Mia as a replacement for Liza. When Liza wrongfully thought Mia was Adam’s accomplice, she pushed her out of the attic window.
Colby still loved her aunt and her mother and could not bear to see them fight. She arranged for them to see each other at Christmas time. The face on meeting forced the women to reconcile their differences.

2003: Liza and Adam decided to separate. Colby would spend most of her time with Liza.

2004: When Liza saw what JR had become as a result of Adam’s influence, she grew fearful for Colby’s fate. Liza decided to run away with Colby. Tad Martin arranged a new life for them away from Pine Valley.

2005: In New Orleans, Liza offered Jamie Martin and Babe Chandler a place to hide from Adam and JR. The Chandler men had been tracking them down after they they learned that Babe and Jamie had kidnapped a very much alive Adam Chandler, III, from his adoptive parents in Llanview. Though Adam and JR were able to trap Babe and Jamie, Liza and Colby successfully slipped out of town.

2006: A delinquent, 15 years-old Colby ran away from Liza and landed in Pine Valley. While eluding the police for stealing a car, she stumbled on the body of Dr. Greg Madden, buried under a bench in the park.
Adam was overjoyed to be reunited with his daughter, but even he was not ready for the demands it took to keep Colby happy. Adam planned a blow-out Sweet 16 for Colby. Krystal Chandler, Babe's mother and Adam latest wife, forced Colby to share the party with Sydney Harris, Winifred’s niece. Sydney and Colby had a very antagonistic relationship. It stemmed from their shared affections toward Sean Montgomery.
Colby stowed away on Jackson Montgomery’s yacht as a post Sweet 16 party. After some heavy drinking, Colby lost her virginity to Sean. Distraught, she crashed the yacht into the harbor. Afraid of the consequences, Colby hid in the Chandler tunnels.
Colby overheard Babe, now married to JR again, talking about how she had slept with Josh Madden. Coming out of hiding, she told the authorities that Josh had molested her, the night Babe and Josh slept together. In order for Babe to exonerate Josh, she would have to admit the truth to JR.

2007: Colby reprioritized her life after Dixie Cooney and Babe were both killed by the Satin Slayer. Colby was a source of comfort for Krystal as she mourned the loss of her daughter. When Krystal revealed the baby she was carrying was Tad’s and not Adam’s, Colby acted surprisingly out of character by refusing to side with her father or Krystal. Adam lashed out by disowning everyone who had kept the secret from him.
Krystal went into labor at Chandler Mansion after a heated argument with Adam. Adam walked out on Krystal. Colby helped her step-mother give birth to a baby girl. Tad and Krystal named the baby Jenny Colby Martin. They offered to let Colby move in with them as she dealt with her changing feelings for her father.
Colby and Sean’s blossoming romance was compromised with the arrival of Ava Benton. Sean admitted that he had slept with Ava. Adam hired Ava to plant drugs on Sean. Colby was arrested because she was wearing his jacket with the planted drugs. When Colby found out what Adam had done, she further pushed her father away.
Adam suffered a heart attack. Colby decided to help her father with recovery. She worried because he was still fueled by his hatred for Tad and Krystal’s new relationship.

2008: Colby and Sean’s relationship ended after he admitted to cheating on her with Hannah Nichols. Colby threw herself into her work as volunteer at Pine Valley Hospital. She had a crush on the young Dr. Frank Hubbard. She became a target for the Robert Gardner, a crime lord who had wrongfully believe the Hubbards to be in possession of a priceless diamond.
Colby’s new friend Dre Woods turned out to be the son of US Attorney Samuel Woods. Dre had ran away from home because of his father’s thirst for a Senate seat. Colby introduced Dre to Frankie’s sister, Cassandra Foster. Cassandra and Colby had become fast friends.
Adam gave Colby and new car and access to the Chandler lodge on her eighteenth birthday. She had come into her inherited Chandler stock and Adam wanted to keep his daughter on his side of the proxy. Colby invited Cassandra and Dre to the cabin for an impromptu party. After Colby drank too much, Dre volunteered to drive the trio home. He hit Richie Novak with Colby's car. They thought they had killed Richie. The three promised to keep the secret of the night between them.
Their cover was blown when Petey came back to town and spotted blood on Colby’s bumper. Colby wanted Petey to stay out of her mess. He used the incident to get close to Colby. When Colby finally told Adam, he tried to blame the crime on Dre. It was later revealed that Richie was already dead when Dre ran him over. Annie Lavery had killed Richie with a crowbar. The ordeal almost sunk Colby into alcholism like her other siblings. It would be Krystal who helped her cope with her problems.
Petey continued his infatuation with Colby. He went so far as team up with Adam to sabotage Babe’s new fragrance, Bella, so long as he helped her win over Colby. Colby and Petey grew closer when a tornado stormed through Pine Valley. Colby made it clear she was only ready to be Petey’s friend, just like they always were.
At the hospital, Colby met war veteran Brot Monroe. Brot was considered AWOL and was hiding in Pine Valley. Colby helped reunite Brot with his former fiancée, Taylor Thompson.