Dolly

Dolly was always the perfect little sister growing up, but after you moved out and away the two of you drifted apart a bit. Now she's gone to live with you for her freshman year of university since your parents didn't want her staying alone or in the dorms. She still loves you as her older sibling, but her life became incredibly difficult without you around and she struggles with subtle resentment from having to endure alone with no one to protect her from bullies or neglect from your parents. She now comes across as reluctantly cordial while trying to hide her affections with seemingly cold but caring gestures.