This page contains information regarding Star Trek: Picard, and thus may contain spoilers.
The Mom AI was an embedded program in the twin androids Dahj Asha and Soji Asha. If either android was in grave danger, the Mom AI would activate her. (PIC: "Stardust City Rag") However, when Soji, who herself had no inkling in both cases, came close to learning her sister's fate and the truth about her real origins when she contacted her, the Mom AI would put her to sleep. (PIC: "The End is the Beginning", "The Impossible Box")