<P> Brennan's personality undergoes significant changes throughout the course of the series . Her thinking becomes less rigid in later seasons, something which is observed by Dr. Gordon Wyatt, who notes that she is now able to distinguish the difference between accuracy and truth . In season 4, Booth takes her along to his interrogations and helps her learn how to set aside her scientific perspective and relate with the victim's family and suspects on a more interpersonal level . She is also able to put aside her rationality to support her friends in sometimes irrational pursuits, such as Angela's quest to raise money to save a pig from slaughter, and to comfort Booth, even using science or quoting directly from the Bible to rationalize his religious beliefs . Her sensitivity and empathy towards others are also much improved, seen quite strongly when she comforts his grandfather, and when she attends a funeral so that the victim's single mother won't be alone . She also displays more "typical" human emotions when in extreme stress . One example of this is her fear of snakes in "The Mummy in the Maze," when a girl is in the process of being scared to death in a room, the floor teeming with snakes . This goes against her empirical nature, as, when Booth tells her that the snakes aren't venomous, she states that she is aware, but still refuses to step in the room, causing Booth to carry her on his back . </P> <P> Brennan begins to feel both dissatisfaction and discomfort with her work toward the end of the fifth season . She also sees some futility in her work, stating that no matter how many killers they catch, there will always be more . To help her gain new perspective, she later decides to head up an anthropological expedition to Indonesia for a year to identify some ancient proto - human remains, after mulling it over during the episode . However, 7 months later, she and everyone else return to D.C. in order to save Cam's job, and they all decide to stay . </P> <P> As season 6 progresses, Brennan must confront her feelings for Booth, whom she rejected in the 100th episode from the previous season . Having returned from 7 months of introspection, she has come to terms with her romantic affection towards him, even admitting that she regretted not having given them a chance together, midway through the season . However, Booth returns from Afghanistan with a new love interest, war correspondent Hannah Burley, whom Brennan befriends . When Hannah rejects Booth's marriage proposal, Brennan must help him through the emotional fallout . </P> <P> In the second to last episode of season 6 Booth and Brennan had sex, consummating their relationship, and it is revealed in the last few moments of the season finale that as a result, Brennan has become pregnant, with Booth the father . Throughout the episode ("The Change in the Game") Brennan has been seen asking Angela questions and making comments that make her seem excited and apprehensive; when she sees that Booth is happy with the news, she also seems overjoyed . This reflects her earlier desire to become a mother, circa season 4, as well as her desire that Booth be the father of the baby . </P>

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