Lovily K. Johnson
Lovily K Johnson is accused of killing her baby son Noah Facebook / Lovily Johnson

A young mother accused of leaving her baby strapped in a car seat for several days in 30C temperatures while it starved to death may not be mentally fit to stand trial.

Lovily Johnson, 22, is charged with first-degree murder and first-degree child abuse following the death of her son Noah Edward Johnson in July. Police were called after she walked into a Michigan hospital carrying Noah's corpse.

Prosecutors allege she restrained her son in a car seat at an apartment on McKee Avenue, Wyoming, and left the six month-old baby without any sustenance or air conditioning in the mid-summer heat for over two days.

They contend that she returned to the flat several times during the period and smoked cannabis on multiple occasions.

Staff at DeVos Children's Hospital were stunned when Johnson arrived with Noah, who was obviously dead and had been for some time on 19 July. Johnson has another child: a daughter, aged two, who has been taken into state care.

If convicted, the mother will face mandatory life imprisonment. A court -ordered forensic examination found that she was mentally competent and should face her criminal charges.

However, her attorney Jonathan Schildgen has demanded that she is sent for an independent examination.

"Mr. Schildgen indicates he wants to request an independent forensic to determine her competency because he has concerns about the report,'' said Judge Steven Timmers.

"I think that's appropriate,'' he added, adjourning the case until 6 December, WZZM13 reported.

When Johnson initially appeared in court in July, she did not appear to understand the charges being read out by Timmers. He had to clarify, saying: "Well, let me make it really clear. They alleged you killed a young child and that you physically abused it. Does that make sense to you?''

"Yes sir,'' Johnson replied.

Lovily K. Johnson
Lovily Johnson walked into a hospital with her dead baby Facebook / Lovily Johnson

Her Facebook page suggests that Noah was born in early January of this year. Messages from family members at the time complain that they had not been informed about the pregnancy.

On 10 June, Johnson made an apparent reference to Noah's father absconding from his paternal responsibilities, when she wrote: "How U A Man & [don't care] About Yo Own Seed! Sound Like A Weak Bi**h To Me !"

The Detroit Free Press reported that she was the victim of domestic violence in 2016 carried out by the father of her daughter. It is unclear if this is also Noah's father.