Details: Lucas has been in love with Peyton since his childhood but she was dating his brother. After they broke up Peyton and Lucas had a complicated relationship/ friendship. In Season 4 Peyton admits to Lucas that she loves him, overwhelmed and shocked he says "oh" but after the State Championship he has a moment of clarity and he realises he wants to be with Peyton. After graduation Lucas visits Peyton in LA and he proposes to her, she refuses. After Lucas almost marries another girl, Lindsey Stauss, he chooses Peyton and that get engaged in Las Vegas. Peyton finds out she's pregnant and Lucas and Peyton find out Peyton has Placenta Previa meaning she could die if she had the baby. Peyton has the baby anyway and after she is born Peyton and Lucas leave Tree Hill.
Details: Lucas Scott is the loving father of Sawyer Scott. Originally uncertain about whether to keep the child, due to the life of his wife being at risk, Lucas soon took to the idea of being a father and aims to be a father like his uncle, Keith Scott, was to him. During his wife's pregnancy, Lucas created a nursery for his child to surprise his wife. After Sawyer was born, Lucas and his family departed Tree Hill to start a new life with their new family.
Details: Karen raised Lucas alone after being abandoned by Dan after she got pregnant. They have a very close relationship. Lucas does feel guilty at times that she has sacrificed so much to provide for him but she always insists that she would not change a thing. Lucas was thus always supportive of Karen having her own life and her own dreams as well as a relationship of her own. Though he had always clearly hoped she would end up with Keith, fate had other plans. He helped her as much as he could when Lily was born. After the birth of his own child, he and Peyton escaped the drama and history of Tree Hill to travel with Lily, Karen and her new husband.
Details: When Dan abandoned Karen, Keith stepped up and became the needed father figure in Lucas' life. Because he loved both of he was willing to put his own dreams and plans on hold to support them. Lucas worked after school at Keith's Auto Shop. It was through that job that Lucas had his first fateful conversation with his long-time crush and future wife Peyton Sawyer. Though they were estranged for a time over the whole Jules fiasco. When Karen and Keith got engaged and he planned to adopt Lucas. All his childhood dreams seemed to be coming true, but it ended tragically when Keith made the ultimate sacrifice to protect Lucas during the school shooting. It was the most painful event of Lucas' life and permanently destroyed his relationship with Dan when the truth was revealed. Lucas honored him the best way he knew how, by becoming the type of man Keith raised him to be. He kept Keith's ring so so he could give it to the woman he would spend the rest of his life with.
Details: Lucas and Nathan are Half-Brothers, Same father different mothers. At first they didn't like each other. They did not interact much until Lucas joined the basketball team. Dan encouraged Nathan to make Lucas' life miserable and drive him from the team so he would not be a threat to his position. It didn't work, and once Nathan started dating Haley he truly changed his ways. Lucas was one of the few to fully support his young marriage to Haley from the start, viewing Nathan as his true brother and knowing their love was the real deal. Mostly they had a great relationship past that point. He was supportive of him when Haley left on tour, though he objected when Nathan gave her the cold shoulder for a time after her return. When Nathan and Haley went to a small college Lucas moved in with them to help raise their son Jaime. Even though it proved to be costly to his own personal life. He chose Nathan as his best man for both his weddings
Details: Lucas was both Jamie's uncle and godfather. Jamie was born shortly after the death of Lucas' uncle Keith with whom he had a very strong relationship with. Due to this Lucas tried to be like Keith. And during Jamie's early years when his parents were in college Lucas helped to raise Jamie. And when Nathan was diagnosed with depression after his accident he stepped up even more. But after Lucas' daughter was born Lucas and his family started to travel the world, so Jamie didn't see Lucas as much as he wanted although they did remain in contact.
Details: Haley and Lucas were best friends since childhood, considering themselves social outcasts up until junior year of High School. Their relationship was never anything but platonic. When Haley first got involved with Nathan, it threatened to drive a wedge between them as the brothers were bitter rivals at the time. But Haley brought out the best in Nathan. It was through her that they became close friends and true brothers. After getting over the shock, Lucas was fully supportive of their marriage, knowing their love was true. He remained Haley's closest friend and supporter even when others were turning their backs on her. After they left school Lucas put his own dreams on hold to help them raise Jaime, much as his own uncle had done for him. Even after leaving Tree Hill. Lucas returned to offer help and moral support when Nathan went missing.
Details: Dan was Lucas' biological father but abandoned him before he was even born. He and no role in the first 16 years of his life. But when Lucas joined the basketball team and threatened to usurp Nathan's position, he turned the two against each other. Despite this the brothers formed a close relationship. They got along better after Dan's heart attack and Lucas even moved into Dan's house for a time. Lucas was relying on Dan to keep secret the fact that they shared the same potentially fatal heart condition. As it turned out each was plotting against the other, a game Dan won in the end. But despite this, Lucas risked his life pulling Dan out of the fire at the dealership, a choice he regretted many times since. The two did not truly repair their relationship until until after Keith death. When Dan was making a serious effort to atone for his past mistakes. But when Lucas discovered the truth about Keith's murder it destroyed their relationship forever. Lucas was notably the only close family member who refused to accept he had changed or to visit Dan when he was dying, something Dan understood completely.
Details: After a rather embarrassing first meeting, Larry made it a point to get to know Lucas, noticing Peyton's romantic interest in him. They became friends quickly, sharing a love of books, Peyton found this embarrassing. Lucas and Peyton were both in an awkward place when Larry briefly dated Lucas' mom Karen Roe. Since they had just recently split after their disastrous first love affair. From their first meeting, Larry could tell Lucas was very protective of his daughter. So he trusted Lucas to look after her while he was away at work. Lucas in turn helped Larry to see how lonely Peyton got when he was away and Larry from then on spends more time at home. Larry was eternally grateful to Lucas for saving Peyton's life during the school shooting. He was unable to make it to their wedding due to the short notice. But was almost certainly delighted to have Lucas as his son-in-law and to meet his first grandchild.
Details: Peyton was very upset when Ellie appeared in her life and revealed she had been adopted. Lucas helped her to cope with this as she tried to decide if she would let Ellie into her life. It was Lucas who first learned she had breast cancer. Ellie did not want that to influence Peyton's decision. But in the end that was what allowed the two to become very close in the weeks before her death. Peyton would always be grateful for this, despite the pain of losing another mother. Lucas helped her though her grief, But admitted he did not really understand how painful it was for her until he lost Keith a few weeks later.
Details: Mick was Peyton's birth dad but was reluctant to admit it when he paid her a surprise visit. She and Lucas were both big fans of the music legend and she hoped to introduce them, but it never happened as Lucas was busy with the launch of his second book. When he returned Peyton had already cut Mick out of her life, finding him very disappointing as a father.
Details: Lucas became suspicious of a guy who suddenly appeared claiming to be Peyton's long-lost brother. He asked the police to investigate and discovered the guy was an impostor and her obsessed internet stalker. Together Lucas and the real Derek saved Peyton from "Psycho Derek's" first attack. But Peyton was deeply traumatized. Upon learning thatl Derek was a Marine, he persuaded her reluctant brother to help her conquer her fears, which he did with tough love and lessons on self-defense.. Lucas and Derek liked and respected each other, but did not have the chance to get close before Derek shipped out to Iraq. But Derek helped Peyton to stop being so emotionally dependent on others and to have the self-confidence to confess her true feelings to Lucas, leading them to finally become a couple. Upon his return from his tour of duty, Derek seemed pleased when his sister told him of her engagement to Lucas. He later gains a niece through their union
Details: Andy was his mom's professor when she went back to school and the two began dating. The two guys became good friends and worked together in a effort to bring down Dan Scott, though it failed. Karen went overseas to be with him for a while, but returned home upon realizing her feelings for Keith. After Keith's murder and the birth of Lily Karen and Andy re-connected. Lucas was genuinely happy for them, not wanting his mom to be lonely and he recognized Andy was a good father figure for Lily. Lucas stayed with them on their yacht for a time to recover himself after being left at the altar. After his marriage to Peyton and the birth of Sawyer, the new family decided to travel the world with them and escape all the past traumas of Tree Hill
Oliver and Cynthia Roe
Relationship: Maternal Grandparents
Details: Karen's parents cut her off when she got pregnant at 18. So it's doubtful he had any kind of relationship with them
Royal and May Scott
Relationship: Paternal grandparents
Details: Though Lucas had no idea, Royal maintained a friendship with Karen and would ask after Lucas whenever he visited Tree Hill