<Li> Tom Marin (Roark Critchlow) (seasons 1--2, 4--5) is Hanna's father . He divorced Hanna's mother, Ashley, after having an affair with Isabel, his current wife . When he comes to Rosewood to visit Hanna, he begins to grow close to Ashley once more, something which is encouraged by Hanna . Tom eventually sleeps with Ashley, but she breaks things off with him when she realizes that he will never change . His wedding to Isabel is interrupted by Hanna, who reveals his affair with Ashley to Isabel . Despite Hanna ruining Tom's wedding to Isabel, Ashley reveals to Hanna that Tom still married her . Tom later reveals that he will be moving back to Rosewood with Isabel and Kate so he can be closer to Hanna . </Li> <Li> Kate Randall (Natalie Floyd, later Natalie Hall) (seasons 1--2) is Isabel's daughter and Hanna's stepsister . Although Hanna is friendly to Kate at first, she begins to resent her . Kate is shown to possess a malicious streak, with a willingness to use manipulation for her own purposes . Hanna had said some unkind things about Kate, but apologizes to her . Kate pretends to accept the apology, but makes comparisons of how to break in horses and how she would break in Hanna . She humiliates Hanna after getting her drunk at their parents' rehearsal dinner . Even though Hanna stopped Isabel's wedding to her father, Kate still becomes Hanna's stepsister when their parents get married at the courthouse . Tom later moves back to Rosewood with Isabel, and Kate is enrolled at Rosewood High . It appears that Kate actually wants to be friends with Hanna at school, but she was really trying to look like an innocent victim, even sending the school a naked photo of herself and framing Hanna for it . But after finding out the truth, Hanna neutralizes Kate for a time . </Li> <Ul> <Li> Lucas Gottesman (Brendan Robinson) (seasons 1--3, 5--7) was an unpopular student at Rosewood, who harbored an unrequited crush on Hanna, with whom he developed a friendship . Having been frequently tormented by Alison, he often expressed his happiness at her death, going so far as to destroy Alison's memorial, believing her cruelty shouldn't have been forgiven posthumously . Although initially angered by Hanna's rejection of his romantic feelings, he eventually accepts it and even befriends Caleb . He seeks Hanna out for dating advice after he becomes involved with a girl named Danielle, however, it is unclear if any relationship developed between them . Soon afterward, due to a series of misunderstandings and coincidences, the Liars suspect Lucas may be "A" 's helper . It is later revealed that Lucas had gambled away thousands of dollars of Caleb's savings . Following this, his friendship with Hanna and Caleb is severely strained, and Lucas grew increasingly more troubled . It was revealed in the third season that he had been visiting Mona at Radley, because she had discovered he was selling test answers and was blackmailing him into working on the A-Team as her personal assistant . He moved away at the end of season 3, out of fear and as a way to start over . Mona soon reveals to the Liars that it was he who gave Emily the massage as "A". He returns to Rosewood in season 5 and begins helping Mona to take down Alison . After Mona's supposed death, Lucas begins helping the girls to stop Alison, who they believe killed Mona . Lucas is not seen after this but is revealed to have attended prom with Jenna Marshall . </Li> <Li> Gabriel Holbrook (Sean Faris) (seasons 4--5) is a Pennsylvania State Police Officer and the detective assigned to Darren Wilden's murder case . </Li> </Ul> <Li> Lucas Gottesman (Brendan Robinson) (seasons 1--3, 5--7) was an unpopular student at Rosewood, who harbored an unrequited crush on Hanna, with whom he developed a friendship . Having been frequently tormented by Alison, he often expressed his happiness at her death, going so far as to destroy Alison's memorial, believing her cruelty shouldn't have been forgiven posthumously . Although initially angered by Hanna's rejection of his romantic feelings, he eventually accepts it and even befriends Caleb . He seeks Hanna out for dating advice after he becomes involved with a girl named Danielle, however, it is unclear if any relationship developed between them . Soon afterward, due to a series of misunderstandings and coincidences, the Liars suspect Lucas may be "A" 's helper . It is later revealed that Lucas had gambled away thousands of dollars of Caleb's savings . Following this, his friendship with Hanna and Caleb is severely strained, and Lucas grew increasingly more troubled . It was revealed in the third season that he had been visiting Mona at Radley, because she had discovered he was selling test answers and was blackmailing him into working on the A-Team as her personal assistant . He moved away at the end of season 3, out of fear and as a way to start over . Mona soon reveals to the Liars that it was he who gave Emily the massage as "A". He returns to Rosewood in season 5 and begins helping Mona to take down Alison . After Mona's supposed death, Lucas begins helping the girls to stop Alison, who they believe killed Mona . Lucas is not seen after this but is revealed to have attended prom with Jenna Marshall . </Li>

Who plays ally's brother on pretty little liars