Jessica Weaver, 35, was arrested and charged with injury to a child by omission last week following an investigation into the death of her three-year-old son Anthony Leo Malave.
Back on 13 May, Ms Weaver had taken Anthony to Camp Cohen Water Park in Texas.
According to a criminal complaint affidavit, several witnesses told police they saw the mother ignoring her child and being inattentive to him while he was playing in a four-foot-deep area of a pool at the park.
The witnesses said they saw Ms Weaver sitting on her phone and “never looking up”.
While people said they saw the little boy “spitting chips” into the pool, they said that Ms Weaver was “singing along to a song that was playing and she was laying down, looking at her phone approximately seven minutes before the child/victim was getting pulled out of the water”.
Other witnesses said she was encouraging her son to leave her and go into the pool alone.
The toddler was seen going down the pool steps by himself and playing alone in the pool while she walked away, the affidavit – seen by El Paso Times – states.
At around 5.09pm, a lifeguard spotted the little boy drowning in the pool and pulled him out of the water.
Witnesses said that Ms Weaver didn’t immediately react to the lifeguard blowing the whistle for everyone to leave the pool.
Instead, “about five minutes” passed before she ran over to her child, the documents state.
Anthony died in hospital one day later.
In total, 18 lifeguards had been working at the water park that day.
The park was not at its maximum capacity of 1,460 people, with around 466 people there on the day, the criminal complaint states.
Officials said that life jackets were available for the toddler to wear, but he did not have one on.
Signs around the pool also stated that children aged six and under “must be directly attended by a swimming adult” at all times and “must be supervised by an adult within arm’s reach”.
Ms Weaver was arrested on 22 September in her home state of Indiana and was booked into El Paso County Jail.
She was released on a $100,000 surety bond.
Now, her attorney is arguing that the mother is being unfairly accused of her son’s drowning in retaliation to her filing the lawsuit.
El Paso District Attorney Bill Hicks hit back at the claims in a press conference last week.
“Every single baby death is reviewed,” Mr Hicks said, explaining that each case is examined by prosecutors in collaboration with police and each prosecution is treated on a case-by-case basis.
“I’m not gonna lure myself to a back and forth with a civil attorney,” he said.
“This is criminal proceedings. It’s the state of Texas versus Ms Weaver. I don’t have anything to say to him.”
The district attorney also called the suit a “political stunt” and said that “a lifeguard is not a babysitter”.