As a young adult, "Days of Our Lives" viewers watched Lucas struggle with his alcohol issues, as well as some big family matters. Although Lucas was close with his mother, Kate, he was stunned to learn that his biological father was none other than Bill Horton and that Billie and Austin Reed were actually his half-siblings, per ShareTV. According to Soap Central, Lucas had a tough time processing the information and he felt very betrayed by his mother. The situation put a strain on Lucas and Kate's relationship. However, the Horton family was more than happy to embrace their newest member.

The Horton family is one of the most prominent in Salem with beloved heads of the family, Tom and Alice Horton. Other notable members of the family include Doug and Julie Williams, Hope Brady, Jennifer Horton, and Mickey Horton, as well as their individual families (via Live About). Eventually, Lucas grew close with his newfound family members and even changed his last name to Horton. Shortly after, Lucas' son, Will, also changed his last name.