Answer the following question: Given the following context:  Mom and Dad tells the story of Joan Blake, a young girl who falls for the pilot Jack Griffin. After being sweet talked by Griffin, she has sex with him. The girl requests "hygiene books" from her mother Sarah Blake; however, the mother refuses because the girl is not yet married.  The girl later learns from her father Dan Blake that the pilot has died in a crash. She tears up a letter she had been writing to him, and lowers her head as the film fades into intermission. The film resumes at the point when the girl discovers that her clothes no longer fit, sending her into a state of despair.  She takes advice from her teacher, Carl Blackburn, who had previously been fired for teaching sex education. Blackburn blames her mother for the problem, and accuses her of "neglect[ing] the sacred duty of telling their children the real truth."  Only then is the girl able to confront her mother.The film then presents reels and charts that include graphic images of the female anatomy and footage of live births – one natural and one Caesarian.  In some screenings, a second film was shown along with Mom and Dad, and contained images portraying syphilis and venereal disease.  Mom and Dad is believed to have had a number of endings, although most typically concluded with the birth of the girl's child, sometimes stillborn and other times put up for adoption.  answer the following question:  What is the full name of the person who requests "hygiene books"?
Answer:
Joan Blake