Kathleen was Cass's first true love. His love for her changed him from the free-wheeling playboy into the responsible man he is today. Much of their courtship was full of excitement and laughter. Neither took life too seriously and both enjoyed one escapade after another.
Cass met Kathleen in 1984 when she was Felicia's personal assistant. He was obsessed with Cecile at the time and recruited Kathleen to help him find her. They found her in Majorca, where they all got kidnapped then poisoned. When Cass returned home without Cecile, Kathleen was there to mend his broken heart.
Back in Bay City, Cass avoided a loan shark, Tony the Tuna, by dressing as a woman. Kathleen tried to scrape together the money by pawning her mother's antique cameo brooch and betting the money on a horse, which lost. To pay him back, Tony forced Cass to instruct his punk niece Dee in the ways of high society. Dee found herself enamored of Cass, and Kathleen felt pushed out of the picture. They split up in the spring of 1985, but quickly reunited.
Kathleen was crippled at the hands of Carl Hutchins while she and Cass were trying to protect an ancient Egyptian artifact. She kept Cass at arm's length. But with the help of his puppet, Mickey, he was able to convince her he wanted to marry her no matter what.
Kathleen exercised every day to be able to walk down the aisle during the ceremony. She was able to accomplish her goal, but upon arriving at the altar she found that the groom was missing. Cass had been kidnapped by his old flame, Cecile DePoulignac.
After two months of heartache and adventure, Cass and Kathleen were reunited. They married in November of 1986. They left for their around-the-world honeymoon the next month, and remained away from Bay City for six months.
When Cass returned to Bay City in the summer of 1987 he broke the devastating news that Kathleen had been killed in a plane crash. It took Cass several years to recover, but eventually Cass found love with another woman, Frankie Frame, and married her in 1990.
Kathleen returned to Bay City in January of 1991 to visit her cousin, Jake McKinnon, who had recently been shot. Frankie discovered her and Kathleen admitted she had been in the witness-relocation program for the past three and a half years for testifying against Carl Hutchins. Cass's marriage to Frankie was deemed invalid, and he was at a loss over which wife to choose.
He reunited with Kathleen because of the history they shared, and because he felt it was the right thing to do. But they had both changed too much over the years. Cass was no longer the adventurous thrill-seeker he once was, and Kathleen missed the man she had fallen in love with. Cass told Kathleen that it was over between them. Devastated and unable to live in Bay City without Cass as her husband, Kathleen moved to New York City in November 1991.