St Joseph Police say Armstrong neglected the child, who died December 13 of malnutrition.
In court documents investigators say the 22-year-old mom failed to provide health and sanitary living conditions, food, nourishment and medical care for the baby, which they say resulted in his death.
Associate Circuit Judge Keith Marquart did not rule on a motion to deny bond for Armstrong.
Bond is currently set at $50,000, but Defense Laywer Susan Rinne has filed a motion to reduce bond. Prosecuting Attorney Dwight Scroggins filed a motion earlier this week to deny bond.
The motions will likely be heard by Judge Daniel Kellogg, who has been assigned the case in Circuit Court. The case is scheduled for arraignment January 15.
Abuse or Neglect of a Child Resulting in Death is a class A felony. The punishment upon conviction ranges from ten to 30 years or life in prison.