What is Perry Smith's sister's name?

In a letter that Perry
Smith's father writes to get him released from the Kansas State Penitentiary, he describes
Perry's only remaining relative (besides himself) as a sister called Bobo, who lives with her
husband. "Bobo" is a nickname for Barbara, also known as Mrs. Frederic Johnson. Perry
also finds a letter that she wrote to him in which she tells him about her children and then
writes that Perry's wrongdoings are not their dad's fault. She says, "What you have done,
whether right or wrong, is your own doing." She believes that Perry is intelligent but that
he must accept responsibility for his life and not blame their father for what has happened to
him. Perry tells Dick that he "loathes" his sister and even wishes that she had been
in the Clutter house so that he might have killed her. Perry Smith has lost contact with her
sister at the time of the Clutter murders. She lives in a middle-class home in San Francisco,
and she tells the detective not to tell Perry where she lives, as she's afraid of him. Perry and
Dick told the police that they were with Perry's sister in Fort Scott on the night of the
murders as an alibi, but Perry's sister does not live in Fort Scott.