A Massachusetts woman facing trial for three babies found dead inside her filthy home gave birth to at least one live infant before it later died, her attorney said Friday.

Erika Murray currently faces charges including fetal death concealment after police found the remains of three babies inside closets in her Blackstone, Massachusetts, home in September, the Associated Press reported. The manner of death and how old the babies were are to be determined by the state medical examiner.

The 31-year-old's attorney, Keith Halpern, said his client told investigators she placed one of her babies in a bassinet to take a nap, according to the Boston Herald. When she returned about two hours later, the child was dead, Murray allegedly told police.

Investigators found one baby in a backpack inside a bedroom closet and the remains of two other babies in another bedroom closet, the AP reported. Prosecutor John Bradley said on Tuesday that since the remains of two of Murray's babies were wearing diapers and clothing, this indicates they were not stillborn.

"They had diapers on. They had onesies on. They were clothed, which would certainly seem to prove that at least two of the babies were alive for some period of time before they died," Bradley said according to the Boston Herald.

But Halpern said just because two of babies were clothed does not mean they were alive at birth. Murray, who has four other live children, has shown signs of mental illness and needs to undergo a mental health evaluation, Halpern said.

It was Murray's four children that led police to the grim discovery inside her squalid Blackstone home. In August, her 10-year-old son sought the help of a neighbor to quiet a crying baby, the AP reported. The neighbor entered the home to find a 5-month-old and a 3-year-old in separate bedrooms, covered in their own feces. 

Massachusetts Department of Children and Families swooped in and removed the four children from their mother's home. Police later returned with a search warrant and found the dead babies after interviewing the two eldest kids, ages 10 and 13.

Murray reportedly hid the existence of the youngest children from their father Raymond Rivera, who was also her live-in boyfriend, by making him believe she was babysitting them.

"There are people who are skeptical of mental illness being raised as a defense in any criminal case," Halpern told the AP.

"But if you don't believe that a woman who lives in the squalor that she lived in, a woman who decides to keep two children hidden from the world and who keeps not only the remains of three children in a bedroom closet, but the remains of family pets- if you don't listen to those facts and conclude that she is severely mentally ill, then there's no such thing as mental illness," Halpern said.

Murray continues to be held on $1 million bail.