Alex Browning is the son of Helen and Paul Browning and the half-brother of Hilton Cunningham.
Alex met Mercedes McQueen when she paid a visit to her husband Paul Browning's ex-wife, Helen. Alex answered the door and assumed that Mercedes was the cleaner. They talked as they waited for Helen's return, to which Alex revealed that he had a girlfriend and was a student studying biology and physics. The pair ended up kissing and slept together, but as Mercedes went to leave, Alex discovered that she was his step-mother. He tried to confront her about the whereabouts of Paul, but Mercedes fled.
Alex decided to investigate his father's disappearance and made his suspicions of Mercedes clear, tormenting her. He discovered that Hilton Cunningham, the son of Mercedes's friend, Cindy Cunningham, was his half-brother. Hilton needed a bone marrow transplant, so Alex decided to get tested. Alex discovered that he was a match and donated bone marrow to Hilton, saving his life. A grateful Cindy informed Alex that he was welcome at any time that he wanted to see Hilton, and Alex returned home.