It is thought a new mother may have killed her husband and her baby before killing herself last week in Missouri.
Experts are now considering whether postpartum psychosis had a bearing on the incident where Mary Jo Trokey, her husband Matthew and baby Taylor Rose were killed.
Their bodies were reportedly discovered on Friday (February 2) by a grandparent and police said a gun was also found at the home.
Police Captain Eric Larson has said the bodies were discovered in the same location and there is no evidence to suspect that an intruder entered the home.
He added that it is believed the shooting took place during the night, according to the New York Post.
Mental health experts told the St Louis Post-Dispatch that some mothers suffer from postpartum psychosis due to their pregnancy which can mean they behave irrationally.
Whilst it is thought this could have played a part in the alleged murder-suicide, experts claim it is unusual for mothers suffering from the condition to harm others or themselves.
Authorities are also investigating how the woman acquired the gun.
A relative of the family told the St Louis Post-Dispatch the couple were married for around five years, adding: “They’re just a good, Catholic family. They’re good people."