The mother and grandmother of a two-year-old who police allege was thrown into the Bronx River by his father are suing New York authorities, claiming they were met with a ‘So what’ response when they called 911.

Montrell Williams, 2, disappeared on Mother’s Day following a custody visit with his 20-year-old father, Arius Williams, and his body was found in the East River nearly a month later, on June 11.

Now, the child’s mother, 17-year-old Cierra Carroll, is filing a $60 million lawsuit against the city, claiming that the NYPD neglected to investigate the toddler’s disappearance properly, according to the lawsuit.

Carroll claims she repeatedly alerted police that her son had not been returned but was met with no support, and grew emotional as she detailed her ordeal at a Friday press conference outside the NYPD’s 40th Precinct.

‘They told me not to follow him and to go to the police to file a complaint,’ Carroll said. ‘I told the police that he had a warrant, they said, “So what?”‘

‘And hung up the phone,’ Carroll’s mother, Octavia Roane, added.

Court records say Montrell’s father was captured on surveillance video walking with his young son before allegedly tossing him from the Bruckner Expressway overpass in The Bronx. 

Montrell Williams 2, (pictured) was last seen wearing only a white shirt and diaper, at an apartment building in Hunts Point – about a mile from his home

Williams mother, 17‑year‑old Cierra Carroll (pictured in black), is suing the city for $60 million, alleging the NYPD failed to investigate the toddler’s disappearance

Montrell, 2, vanished on Mother’s Day after a custody visit with his 20‑year‑old father Arius WIlliams, who now faces murder charges 

Arius Williams now faces charges including second‑degree murder and manslaughter, and remains held without bail.

Carroll filed a formal notice of claim, a prerequisite to suing a government entity, on Thursday.

She stood visibly shaken as she held her press conference in the Bronx, surrounded by her mother and a spokesperson for the family.

‘She’s very hurt right now,’ Roane said. ‘The way the police responded, the way they acted towards us, no care in the world.’

‘They put them on notice that this child is in danger. No Amber Alert was issued at all. And, while this child’s life was hanging in the balance, they were pushed to the side,’ the family’s lawyer, Shiraz Khan, added.

The family also alleges they filed multiple missing-persons reports but were repeatedly directed to family court rather than being treated with urgency.

Police say Montrell was murdered on May 10 but that the initial complaint wasn’t reported to the NYPD until May 11, The Gothamist reported.

Mayor Eric Adams said the NYPD’s handling of the case is under review.

The toddler was last seen around 10 p.m. on May 10, wearing only a white shirt and diaper, at an apartment building in Hunts Point about a mile from his home.

Detectives have reason to believe the father threw Montrell into the Bronx River, near the Bruckner Expressway. Pictured: A view of the Bronx River from the Bruckner Expressway

He was last seen around 10 p.m. on May 10 at an apartment building at Hunts Point Avenue and Gilbert Place in Hunts Point (pictured)

The boy was reportedly with his 20-year-old father that day for a scheduled custodial visit. The parents share split custody and visitation rights.

However, when Montrell was not returned, his mother grew concerned.

On May 30, after questioning the father about the boy’s whereabouts, she received a troubling response.

‘She asked where their son was and he made concerning statements,’ a police source told the Daily News. Officials confirmed that the father’s initial statements raised red flags about the child’s safety.

Following initial questioning at a police precinct, the father appeared in Bronx Family Court to answer a warrant for failing to return Montrell in accordance with the custody agreement, according to ABC7.

When he refused to disclose the boy’s location to the judge, he was taken into custody.

Detectives have reason to believe the father threw Montrell into the Bronx River, near the Bruckner Expressway.