Dr. Lance Sweets is a psychologist that works with the FBI, getting feild agents cleared for duty. His past is a dark one, as he was beaten by his parents, and put into foster care at age four. He is an only child. The whereabouts of his father are unknown, but his mother works as a 'psychic' for a carnival in Florida. His foster turned adoptive parents were very good to him, and raised him right, but sadly, they had passed before he entered the series. Even though he had good parents for most of his life, Lance still retained physical and emotional scars from his time with his biological parents.
In Season 3 , he is asked to work with a certain bickering pair after the FBI feels that Booth and Brennan need to be in therapy, since Booth arrested Brennan's father, Max. After awhile, he became Booth and Brennan's fulltime therapist, and the rest of the Squint team seems to be warming up to him as well, coming to him about a whole slew of issues. He does criminal psychology profiles for the Jeffersonian when they have a case, and recently finished a book that he had written about Booth and Brennan's relationship, called 'Bones - The Heart Of The Matter'. One of his idols is Dr. Gordon Wyatt a recently retired psychologist who was Booth's therapist in season 2, after Booth shot a ceramic clown's head on the top of an ice-cream truck. It's Dr. Wyatt, in the S4 episode 'Mayhem on the Cross' that informs Booth and Brennan about the truth of Lance's past, that he was beaten as a child, whipped more specifically.
Lance originally was dating a girl named April, who was older than him and worked at a pet store selling fish. After doing a double date with Boot hand Brennan, April decides that the relationship between her and Lance wouldn't work, and she breaks up with him. In S4, a young, energetic, talkative, and admittedly slightly annoying , anthropologist named Daisy Whick comes to the Jeffersonian as part of the rotation to find a new assistant for Dr. Brennan, to replace Zack. After being so annoying that the gang can't handle her....twice... you find out that her and Lance are dating, and have been since the end of the last episode she was in. After a misunderstanding in which Booth and Brennan thought she was cheating on Lance, and getting married to someone else because they see her in a wedding dress store being fitted, you find out she was fitting a dress for her cousin, who is the same dress size as her. After a small arguement, mostly Lance talking, Daisy tells him the truth about what they saw, and assures him she isn't going anywhere. Even in the AU/Dream S4 episode, Daisy is a waitress at the club that Booth and Brennan run, and even though they aren't together in the beggining, Daisy and Lance end up together by the end of the AU Story/Dream.
