문장 속 she와 her가 가리키는 인물이 궁금해요

“In her counseling practice, Christina often deals with clients who are constantly disappointed and frustrated by their own expectations. Lena, one of the clients she had, would have her counseling sessions after visiting her parents. She would talk about how upset she was that they would only make limited efforts to spend time with her when she made the effort to visit. She discussed with Christina what she expected her parents to do when she went for a visit and worked to change her expectations.”
she와 her가 각각 누구를 가리키는지 헷갈려요. Christina인지 Lena인지 설명 부탁드립니다.