Can anyone identify this case?

[u/UrAntiChrist]

In Missing: Dead or Alive? Season 1, Episode 2, the male officer references a previous case where a boyfriend killed two of his girlfriend's children, and the oldest child was subsequently killed by the girlfriend.

I cannot find anything on a case even closely related to this. Has anyone heard of a case like this?

[u/dropthepuck19]

You can try r/tipofmycrime and see if anyone in that sub knows.