Alexis Davis is a smart and intelligent lawyer. Sonny had asked her to represent him for a while before she finally agreed. She was reluctant at first, but after she got to know him a little better, she became a close friend and confidant. She was able to get Sonny out of many legal problems. In an moment of passion, Sonny and Alexis slept together. Alexis became pregnant. When Alexis' sister Kristina was killed in an explosion at Sonny's warehouse, she cut all ties to her former client. Alexis feels Sonny's life is too dangerous and doesn't want him to be part of his child's life. She named Sonny's daughter Kristina.
Alexis finally told Sonny that Kristina was his daughter, after Kristina became ill with leukemia. Alexis and Sonny shared custody of their daughter. However, Alexis continued to sabotage Sonny's relationship with his daughter and Sonny was not able to spend as much time with Kristina as he would have liked.
When Kristina became a teenager, she struggled with self-esteem issues and had a relationship with an abusive boyfriend. Alexis realized that a lot of Kristina's issued had to do with Alexis keeping Sonny from his daughter. So Alexis encouraged Sonny to have a relationship with his daughter.
Sonny and Alexis agree to be there for Kristina. Alexis has accepted Sonny in Kristina's life. They often consult each other when issues with Kristina arise. Alexis asks Sonny to secretly get Kristina into Yale. Sonny agrees. Kristina is excited when she gets her acceptance letter. Sonny has a goodbye party for Kristina and tells her how much he loves her.
Professionally, Alexis is Sonny's lawyer. Sonny and Alexis also continue to be co-parents and friends for Kristina.