The Ohio case involving 16 children rescued from a deeply troubled household has taken another extraordinary turn: mental competency has now become a central issue for every adult defendant.

Elizabeth Siders, Gary Siders Jr., Gary Siders Sr. and Christina Siders are each facing 16 counts of felony child endangerment following the June 30 discovery of the children at a Hamden residence.

Now, all four defendants have been connected to requests or court orders involving competency evaluations.

The latest development came on August 10, when a Vinton County judge granted Elizabeth Siders’ request for a mental-health evaluation.

Her attorney, J. Thomas Stolly, had filed the request several days earlier, saying he had become concerned about Elizabeth’s mental health after meeting with her repeatedly.

The defense requested two possible evaluations.

The first would determine whether Elizabeth is competent to stand trial.

The second, if she is found competent, would examine whether she could potentially qualify for a not-guilty-by-reason-of-insanity defense based on her mental state at the time of the alleged offenses.

The development is significant because competency is not simply a question of whether a defendant has a diagnosis.

A person can have mental-health difficulties and still be legally competent to stand trial.

The court must determine whether the defendant understands the nature of the proceedings and can communicate sufficiently with an attorney to participate in a defense.

An insanity defense is different.

It concerns the defendant’s mental state when the alleged conduct occurred. Therefore, even if Elizabeth is eventually found competent to participate in a trial, a separate evaluation could examine whether she understood the wrongfulness of her conduct at the relevant time.

At this stage, however, there has been no finding that she was legally insane.

There has also been no finding that she suffers from any specific mental disorder.

Those conclusions would require professional evaluation and, ultimately, legal determinations.

The development comes against the backdrop of allegations that shocked investigators.

Authorities say 16 children, ranging in age from 18 months to 18 years, were discovered inside the family’s Hamden home.

Investigators described the conditions as extremely unsanitary and alleged that the children had been confined to a small room measuring approximately 12 by 12 feet.

Authorities also reported that the room contained human waste and that some of the children required medical treatment after being removed.

The discovery reportedly occurred while authorities were investigating Gary Siders Jr. for an unrelated matter.

What began as another investigation quickly expanded into a child-welfare and criminal case involving four members of the same family.

The defendants have pleaded not guilty.

Their attorneys have also pushed back against some public descriptions of the living conditions and have urged people not to prejudge the defendants before the evidence is presented in court.

That distinction is becoming increasingly important as the case receives national attention.

Another major development concerns Gary Siders Sr.

The 73-year-old grandfather was previously hospitalized and his attorney raised concerns about his health and competency. He was later released under court conditions that include GPS monitoring and other requirements.

The case is still moving toward the grand-jury stage, meaning the current charges could change depending on what prosecutors present and what the grand jury decides.

That process could ultimately determine whether formal indictments are issued and what offenses the defendants will face going forward.

Meanwhile, the 16 children remain at the center of the investigation.

They have been removed from the home and placed under state supervision, where officials are addressing their medical, psychological and educational needs.

Perhaps the most unsettling question surrounding the case is how a household containing 16 children could remain so isolated for so long.

Investigators are examining the family’s history, movements and living arrangements as they attempt to establish how the alleged conditions developed and how long they continued.

The latest mental-health developments could make that investigation even more complicated.

If evaluations conclude that one or more defendants cannot currently participate in a trial, proceedings could be delayed while the court determines what happens next.

And if an insanity defense eventually becomes part of Elizabeth Siders’ case, prosecutors and defense attorneys could face an entirely different legal battle.

For now, the central facts remain unresolved in court.

Four adults have been charged.

All four have pleaded not guilty.

The 16 children have been removed from the home.

And every defendant is now connected to competency-related proceedings.

What began as one of Ohio’s most disturbing child-endangerment investigations is becoming an increasingly complex legal case — one where the next major revelation may come not from the house itself, but from what psychological evaluations reveal about the adults accused of being responsible for it.