Less than a week before Sonya Spoon was charged with suffocating her two young children, police had escorted her to a hospital for an emergency psychiatric evaluation. She had threatened to kill herself and Kayla, her 3-year-old daughter, authorities said Monday.

On Sunday, Kayla and Spoon’s 1-year-old son, Ayden, were found unconscious with plastic bags and duct tape around their heads in the Cheverly home where Spoon, 24, was staying with her mother, police and family members said.

Police and court documents show that Spoon, who had been engaged in several custody battles over Kayla and Ayden, had struggled with mental health issues in the days leading up to the deaths. On Monday, police said they were not certain how long Spoon’s recent hospital stay was or what she might have been treated for.

On Sunday, authorities received a call about 2:15 from the children’s maternal grandmother, Paivi Spoon, that Kayla and Ayden were not breathing, charging documents say.

“Investigators learned from Paivi Spoon that Sonya . . . woke her up and ultimately told her that she killed her children,” according to court records. “Paivi Spoon then found the children with plastic bags and duct tape around their faces and heads.”

Sonya Spoon (Prince George’s County Police Department)

Paivi Spoon removed the bags and tape and tried to administer CPR before rescue crews transported the children to Children’s National Medical Center in the District, where the toddlers were pronounced dead shortly after, according court documents.

Lester Thompson, Kayla’s father, said Spoon was hospitalized for several days before she was released.

But Thompson, 41, said he never had any reason to believe Spoon would harm her children.

“She seemed pretty docile,” Thompson said of Spoon. “Never . . . signs or anything like that. Never.”

Thompson said that he and Spoon broke up soon after Kayla’s birth and that Spoon sought to keep him away from their daughter.

Court records in Calvert County, where Spoon once lived, show a contentious custody battle. A judge had ordered mediation for the couple on several occasions, but the two could never reach an agreement that lasted long. A custody hearing was set for Sept. 23.

Court records also show that Spoon officially had her son’s name changed to Ayden Jonathan Spoon last September because she claimed the child’s father was not involved in the boy’s life. Attempts to reach the boy’s father unsuccessful.

The Prince George’s County police department has taken over the homicide investigation, and Spoon admitted her involvement in the children’s killings, said Maj. Cesar Pacheco, head of the county’s Criminal Investigations Division. Spoon has been charged with two counts of first-degree murder and is being held without bond.

“Foul play was readily apparent,” Pacheco said of evidence found at the home.

While Spoon’s psychiatric history and custody issues are being considered, detectives are still trying to find a motive, Pacheco said.

Maryland officials who oversee state social services have launched a routine, internal review into Kayla and Ayden’s deaths.

“As we do with all child fatalities, the Department of Human Resources has initiated an internal review of this case,” said Brian Schleter, a department spokesman. “We are also working closely with local law enforcement on their criminal investigation into this terrible tragedy.”

Thompson said he is heartbroken at the loss of Kayla, who loved to dance, sing and make up songs about princesses, cats and anything else that crossed her mind.

“There’s no law that can penalize her the way that’s appropriate for what she did to those children,” he said. “She does not deserve to speak the name of my daughter or her son out of her mouth.”

Messages from what appears to be Spoon’s Twitter account shows pictures of Spoon with her two children on cabin trips and at a rodeo. In an Aug. 20 tweet, a selfie with her and Kayla appeared on the account with the caption “My love :)”

In an earlier posting she quotes from the musical group Evanescence and talks about how the group “always gets how I feel during the high and the low times.” The tweet is accompanied by lyrics to a song called “Missing.”

“Please, please forgive me

but I won’t be home again

I know what you do to yourself

I breathe deep and cry out.

Isn’t something missing?

Isn’t someone missing me?”

Arelis Hernández and Jennifer Jenkins contributed to this report.

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