Steinhagen died in December.
A judge determined that Steinhagen was insane and committed her to a mental hospital. She was released three years later and stayed out of the limelight.
"She chose to live in the shadows and she did a good job of it," John Theodore, an author who wrote a 2002 nonfiction book about the crime, told the Associated Press.
Steinhagen had a crush on Waitkus when he played first base for the Chicago Cubs and turned her room into a shrine to him. When he was traded to the Phillies, she became enraged.
The next time the Phillies came to Chicago to play the Cubs, Steinhagen checked into the same hotel the Phillies were staying in and wrote Waitkus a note saying, "We're not acquainted, but I have something of importance to speak to you about."
Waitkus went to her room and was invited in. Steinhagen walked to a closet, said, "I have a surprise for you," then pulled out the rifle and shot him.
Waitkus, sat out the rest of the 1949 season but returned in 1950, helping lead the Phillies to the World Series.