I would posit that “mom” has been brainwashing the boy for some time now thereby robbing his innocence. Millstones come to mind and the Marianna Trench.
Reminds me of that scene from the movie "The Sixth Sense." At Kyra's funeral, her father finds out that her mother had been poisoning her. The child surreptitiously recorded the deed and had the video shown at her funeral, where her stricken father watched.