Robin Charles is the daughter of Dr Daniel Charles. She is an epidemiologist at Chicago Medical Center.

Season 2

Robin joined Chicago Medical Center after helping with a rare infection.

In Generation Gap[1], Charles notices Robin spacing out while staring at a vending machine. He then saw her at the cafeteria where she was worriedly looking for her wallet. She claimed it was stolen and that she'd have to replace all her cards and began panicking, when Dr Charles simply checked the side pocket of her bag and found it for her.

Connor then told Dr Charles that Robin is hearing things and spacing out, after insisting that she heard "rats" in his apartment. He had two exterminators check the place out but she insisted they were there. Charles dismissed him and told him it's normal and told him to leave, but was very worried and didn't want him to know.

Charles went to see Robin in her office afterwards and she told him she was glad he was there. She said she had the droppings as proof that they have rats. She takes out a sealed bag with folded tissues. She unfolded the tissues one by one to reveal nothing. She stared in surprise and said she knew what she saw. Charles was upset and told her that not as a psychiatrist, but as a father he would feel better if she saw someone, and she agreed.

Charles could not treat Robin himself, but Sarah was the one treating her under a different psychiatrist. Sarah tried building a relationship with Robin and told her she could go home. Charles didn't agree with the decision. He went to her apartment after taking her keys and found mouse traps all over the house and the wallpapers and furniture ripped apart. He then stopped Robin from leaving the hospital. Robin didn't want to stay, so Charles resorted to forcing her to stay in a psychiatric hold. Sarah was angered as it ruined the trust between her and the doctors, and Robin said she hated her father for making her stay.

In White Butterflies, a lawyer came to Chicago Medical Center to help Robin get out of psychiatric hold, because she, Connor and Sharon thought that Charles had only put her in there because she was his daughter and he was being paranoid. Robin argued she could live with Connor, who told Charles that he could protect her and take care of her better than Charles did. However, when they get home, they get dinner and go to sleep and Robin has a breakdown that night. Connor wakes up when he hears something break and goes to the living room to find her hitting at nothing with shattered glass on the floor. He tries to get to her but she doesn't seem to see him and runs outside to the balcony, locking him out. He is extremely scared and tries to get her to come back in, but she screams and even tries to jump off at one point, leaving him scared and distraught as he can't do anything.

Season 3

Robyn had a difficult time recovering. Reese, Connor and Dr Charles were concerned about the course of action being taken and got into frequent arguments with each other over this issue.

Robyn was unsure about her wellbeing after being released and had Sarah check her over again after she thought she had 'rats' again on her first day back. She was told it was normal, but argued the tests were wrong. This was until she found that the noises she'd been hearing were real and a result of a broken pipe above her office.

However, she continued to experience difficulties such as paranoia and impulsive behaviour with a lack of control over her actions. She shoplifted at Cornelius's store and he called Connor to come get her. She was upset over her slow recovery and actions that she couldn't control. Connor furiously told Sarah she'd not done her job properly. Robyn was upset and so went to her father for help. She decided to leave Chicago in Ties That Bind with his help to go live with her mother. She left Connor a letter, and he confronted Dr Charles over it and was told it was her idea.