Police say Jessica Brewster admitted to smothering the baby because she feared her mother’s reaction to the pregnancy.
Sylvia Majewska is charged with first-degree murder in the Nov. 23 killings at her home in Oakland County.
Crime Stoppers is now offering a cash reward in the death of the newborn baby.
Sheriff Michael Bouchard says Majewska “came to the conclusion that the son and the child would be better off if they weren’t alive.”
Investigators are working to determine what happened in an Oxford home that led to the killing of a 29-year-old man and his infant daughter.
A preliminary exam from Sierra Tankersley on felony murder and first degree child abuse charges was rescheduled.
Police say the man’s car was in reverse when his brother came running out of the house, yelling for him to stop.
The 24-year-old offered an apology before the sentence was handed down, saying: “This is the single-most deviant act I’ve ever committed.”
A woman and her baby are dead following a two-vehicle crash that left the baby’s 7-year-old sibling in critical condition.
Authorities say the child had hemorrhaging in her brain and eyes as well as alcohol and marijuana in her blood.