Twin toddlers found dead in their bedroom may have starved to death, prosecutors told an Australian court Tuesday.

Prosecutor Michelle Clarke said police officials found the bodies of an 18-month-old boy and girl in a “state of decay” and that they appeared to be malnourished, the national AAP news agency reported.

The gruesome discovery was initially made by an 11-year-old sibling who smelled something unusual in their suburban Brisbane home.

The toddler’s 30-year-old mother allegedly told police she realized they had died on June 8 or 9. When asked by police how they died, the mother allegedly said, “I don’t think I fed them enough.”

She added that she had been suffering from a cold at the time. One of the children weighed just 8.8 pounds, according to AAP.

The unidentified woman and her husband, 28, appeared on charges of failing to provide necessities of life after police found the bodies late Monday. According to court testimony, the children’s father told police he did not realize they had died until Monday, despite walking past their room several times since their death a week earlier.

Clarke said when the bodies were discovered by one of the couple’s four other children, the child told the mother, “I know why you have been crying now.” The older children said they had rarely seen the twins, who had been kept in a front room of the house for most of their lives. The four other children are now in the care of their grandmother, AAP reported.

The couple had been enduring “significant relationship problems” and the children’s father had failed to support them, according to court testimony.

Police prosecutor Sergeant Tina Green said charges would likely be upgraded when autopsy results are returned Thursday.

"It's most likely they are heading towards manslaughter or murder charges," Green told the court.

Magistrate Noel Nunan is holding the couple without bail until Thursday.

"The circumstance of the death of two young 18-month-old children is bizarre, given that both the parents had been in the house for approximately one week since their death,” Nunan said.

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