Mary’s parents were young and her father, Michael, only made $15 per week. A relative of Mary’s mom, Catherine, wrote to a social service agency for help. Unfortunately, their address was disclosed to/learned by a woman.

On May 14, 1930, a woman came to the door and said she was sent by a social worker. She identified herself as “Julia Otis” and was described as 22 years old, well dressed with protruding teeth. She spoke with Catherine and asked if she could take Mary to California with her, for a little while. Catherine refused. “Julia” then promised to return, handed Catherine $2, and left.

“Julia” returned the next day with baby clothes (Catherine was pregnant at the time). She indicated she had arranged for a better job for Michael and offered to take Mary to a store to buy her some clothes and shoes. Catherine gave her consent, reluctantly. Mary Agnes did not want to go with the woman and sobbed. However, she did go and Mary Agnes and the woman never returned.

Two letters were received by the Moroney family in relation to the kidnapping. The first one arrived the day after Mary Agnes was taken.

“Please don’t be alarmed, I have taken your little girl to California with me. I have hired a special nurse to care for her. We’ll be back in two months. By that time you will be on your feet again and will be able to care for her. She didn’t even cry a bit. She is outfitted like a princess. In the meantime, I’ll help all I can to get you on your feet. Don’t worry about her or anything else. When you get this letter we’ll be on our way already. As ever, Julia Otis”

The second letter was received 2 weeks after the kidnapping, from a woman her identified herself as “Alice Henderson” who stated that “Julia” was her cousin and that she was “love hungry” because her own husband and baby died the year before.

No other letters were received. Police said that the handwriting in both letters was the same.

Her kidnapping is the oldest unsolved case of this nature in the files of the Chicago Missing Persons Bureau.