Ruben has been married four times, though one was an annulment. He and Cindy were high school sweethearts, until Cindy purposely got pregnant to "find someone to love her, even if it was just a baby", then when he offered to marry her, she turned down his proposal and told him to stay out of her and their child's life until Adrian was 16, yet he still paid child support for the first sixteen years of Adrian's life, until Adrian snuck into her school file, found Ruben's name, and tracked him down.
As revealed in Back to School Special, when Adrian was six-months-old, Ruben married his first wife and started his own family, which produced a son. According to The Secret Wedding of the American Teenager, Ruben's son currently lives in Mexico with his mother. Since then, he was married three more times. With his third marriage, he married a woman with two sons, and helped raise them from small children to the point that he considered them like his own biological children. However, after Adrian came into his life, his step-son Max began a sexual and romantic relationship with Adrian and his old feelings for Cindy began to surface, until it ended in his second divorce.
Before their marriage, they bought the house next door to the Juergens family from George Juergens, and moved in together. Cindy and Ruben married on February 6, 2010, the same day as John Juergens's first birthday, and unbeknownst to them, Adrian had gotten pregnant by Ben the previous month. When Ruben found out from Leo Boykewich that Adrian was pregnant, he told Cindy and began to try and talk her out of an abortion. He was firmly against the abortion and thrilled when Adrian told him she had decided not to at the last moment, but things between him and Cindy remain rocky, since she did not want Adrian to repeat her past and be pregnant at 17-years-old and blames him for Adrian not terminating the pregnancy.