Sia is responding to estranged husband Daniel Bernad's "outrageous" filing for full physical and legal custody of their toddler son.

The 49-year-old "Titanium" singer said Bernad's emergency child custody request "should be denied in its entirety" because he "provides zero evidence" that their one-year-old son Somersault "Summi" Bernad's safety is "at risk," according to an Oct. 28 filing in Los Angeles Superior Court, which was obtained by USA TODAY.

Bernad "improperly seeks to disturb the status quo by requesting an abrupt and unjustified reversal of the parties’ custodial arrangement by removing Summi from Sia, his primary custodial parent since birth, and placing him solely in Dan’s care," Sia's filing states.

The document was submitted in response to Bernad's filing, which was also reviewed by USA TODAY, claiming "Sia is a serious and immediate danger to our son" because she is an "unfit and unreliable parent struggling with substance abuse and addiction." He also says she was "gatekeeping" his time with their toddler.

Bernad, a radiation oncologist who later founded a ketamine clinic with the singer, claims that while Sia was secretly hospitalized for two weeks in September for an alleged allergic reaction, she'd "tested positive for barbiturates and benzodiazepines with no legitimate medical explanation."

Barbiturates and benzodiazepines are depressants that have sedative and hypnotic effects, typically used to treat anxiety and seizures, according to the U.S. Drug Enforcement Administration. Both are controlled substances that can be prescribed by licensed medical professionals, per the National Institutes of Health.

The information was included in a report prepared by the Los Angeles County Department of Child and Family Services that revealed the hospitalization, he wrote.

But Sia pushed back against his allegations about her addiction, noting they were "unfounded and misleading" as well as an "attempt to weaponize my past sobriety journey."

"It is true that I struggled with drug and alcohol issues more than fifteen years ago," she says in her declaration. "I have been fully sober for over six months and working my program which includes weekly testing and a sober companion."

Bernad asked the judge to compel Sia to submit to random drug testing throughout each month in addition to weekly drug tests. He also requested an allowance of three monitored visits between mother and son each week, as well as $77,245 per month in child support because he is "totally financially dependent on Sia."

In her filing, Sia's lawyer Laura Wasser said the Grammy-nominated singer has paid around $300,000 since their split. The two were married in December 2022 and have been separated since March, when Sia filed for divorce.

'Summi has been and remains safe in Sia’s custody'

Sia's court filing declares "Summi has been and remains safe in Sia’s custody" and casts doubt on Bernad's fitness as a father.

Bernad "has not demonstrated the ability — or even basic familiarity — necessary to meet the developmental, emotional, or daily care needs of a child," Sia's lawyer writes. In his court documents, Bernad includes dozens of monitoring reports from his visits with Summi.

Professionally monitored visits were requested by Sia in response to an investigation by the Los Angeles Police Department and the Los Angeles County Department of Child and Family Services into pornography involving minors that was allegedly found on Bernad's personal hard drive.

"While I understand the investigations of LAPD and DCFS have been inconclusive and now closed, this does not appease my concerns of Summi spending unsupervised time with Dan," Sia writes.

USA TODAY has reached out to the LAPD and the Los Angeles County Department of Child and Family Services, as well as Sia and Bernad's lawyers, for comment.

Court filing: 'Inappropriate images' found in storage unit Daniel Bernad 'never even visited'

Bernad addressed this issue in his filing, claiming "a hard drive containing inappropriate images" had been discovered by Sia's assistant in a storage unit "that Sia and her employees acquired" and which he "had never even visited."

The Child and Family Services Department's investigation was closed due to being deemed "inconclusive" and "unfounded" on Sept. 23, according to a letter attached to the filing. In a separate Oct. 2 email, a detective from the LAPD's Internet Crimes Against Children division appeared to note the case is "closed/suspended due to no evidence of a crime at this time."

If you or someone you know needs help battling a substance abuse addiction, contact the Substance Abuse and Mental Health Service Administration's National Helpline at 1-800-662-HELP (4357).

This article originally appeared on USA TODAY: Sia, ex-husband's custody battle escalates with claims of addiction, child porn

Reporting by KiMi Robinson, USA TODAY / USA TODAY

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