She was born in October of 1965.
From a young age, Alex was raised by her mother because her father left. Her father was also a lawyer and a fairly good one. He came back into her life when he put her through law school.
Her father was an alcoholic, he went to the Greendale Treatment Center when they put Karl Mayes to the prison.
Relationship with Walker
Alex and Walker first appeared as a very unlikely pairing, both professionally and socially. At first, Walker did not seem to want to be bothered with the fledgling ADA as Alex often came to Walker with cases that were not particularly "his kind of thing" to take on. However, as a recurring character in the series, Alex continued appearing more and more in Walker's life both inside and outside of the workplace setting.
It was becoming clear how Alex was becoming attracted to the "stubborn" Texas Ranger as she appeared often during or after episode cases, usually offering a sentimental heart out to Walker as in earlier episodes, Walker has lost many of his friends and acquaintances to death. Alex also seemed to have laid a visible claim on Walker as she verbally indicated her disapproval of Walker seeing other women, especially ones involved in protection-based cases. These relationships which had the potential of flourishing into something more often ended on disheartening notes as either these other women "had to go" or possibly were killed off during the episode's run. This could be seen as having paved the way for the "obvious" choice of Alex Cahill's finally making a relationship with Walker as the series direction pointed more and more to Alex being the "best choice" for Walker.
When the two did become an official couple, Alex often was the target of kidnappings and hostage situations including an episode in which she was assaulted by the psychotic character named "Larue". Ultimately Alex's role in Walker's life expanded more with growing scenes of her visiting the police station usually to flirt and romance with Walker while on the job. This would replace Alex's general in-court appearances and restrict her to more "walk-in" appearances into the police station rather than offer viewers better and more believable scenes of her prosecuting experience. Near the series' last two seasons, Alex and Walker took a more comical backseat as the two were preparing for their wedding and their eventual family. In one episode, Alex took the helm and insisted on giving Walker's house a total make-over as she felt it was much too "masculine" for their new home life together. She also came down with a case of baby-fever and insisted that she and Walker temporarily adopt a baby they found left in a store while they shopped in one of the season's final episodes. Viewers can and could easily see a growing change in Alex's personality as one being very insistent, possessive and quite tailored in the mold of the "damsel in distress" as Walker often saved her life from criminals throughout the 8-year series run.
At first, Alex and Walker did not see eye to eye as we saw in the episode "Till Death Do Us Part" they at first hated each other; or as she put he was way out of line. They first met (probably) at the end of December 1986 (probably 28th) when she was receiving his testimony in court and then she was fairly new to the District Attorney's office. And then they were thrust back at the following New Years party at CD's Bar and Grill. And as sort of a New Years gift he kissed her at the stroke of twelve. (In 1987 she put in prison a guy named Baker, who came back to Dallas in 1993, kidnapped and tried to kill her.)
She somehow grew to like Walker as a friend at first. In the first and second seasons, they were friends. But more and more as trouble gradually crept up on Alex, she and Walker grew more intimate. Soon by season three, their once work-related association became more of a romantic relationship.
Their relationship was like an elevator - with some ups and downs. But after Karl Storm tried to kill Alex during the wedding of Phil Holland and Kim Rivers, Walker proposed to Alex.
They eventually got married (20 May 2000) and have a daughter named Angela (born May of 2001).