FORT WORTH -- A court affidavit released Friday reveals new information into the death of a 1-year-old boy at the hands of his mother's boyfriend.

Nineteen-month-old Armando Soto died of blunt force injuries to the head on Nov. 21, 2017. On Feb. 1, police arrested Derrick Pete Silva, 21, and charged him with capital murder.

Back on Nov. 19, emergency crews were called about the child having seizures at a home on South Freeway in Fort Worth. Soto was taken to Cook Children's and underwent emergency surgery, documents show.

Soto came out of surgery and was placed in a coma, the affidavit said. He was declared brain dead and died on Nov. 21.

His mother told officials that she had put Soto down for a nap and was continuously checking on him when she asked Silva, her boyfriend of two to three weeks, to check on him. She claimed Silva came out of the room carrying Soto, who appeared to be having a seizure, and said he had fallen off the bed, according to the documents.

Medical officials determined that Soto's injuries were much worse than falling off a bed, classifying them as "physical abuse" and "abusive head trauma," prompting Child Protective Services to be called.

The boy's mother also told investigators that Silva told her and other family members he would "take the blame" if anything happened to the child. She added that Silva would tell her son not to cry "like a little bitch" and told him that crying was for girls. He even threatened that if he kept crying, "he would take him to the hospital and have his 'pee pee' chopped off," the affidavit states.

On Dec. 5, police brought in Silva for an interview. At first he told police he didn't know what happened to the boy, then changed his story and said he was afraid he caused the injuries.

While writing apology letters, Silva admitted to punching Soto "two times with a closed fist," the affidavit said.

He revealed that he put Soto down for a nap and gave him a bottle, but he wouldn't stop crying, which "frustrated" Silva. He punched the boy twice "really hard on the back of his head," he admitted, and wasn't sure if the boy's head hit the wall or not.

He said the boy's hands and feed started "twitching" or "shaking" before he left the room to watch television and try "to calm down," documents state.

He told police his cousin heard Soto crying and found him on the floor in the bedroom. He placed him on the bed. When Silva went into the room, the boy was having a seizure, the affidavit said.

Officials at Cook Children's told officers that Soto had "abusive head trauma" and "observed posttraumatic seizure activity."

The affidavit revealed that doctors determined Silva's story to be consistent with Soto's injuries, and stated that "the punches would have had to have been very hard," the affidavit states.

Silva is currently being held on a $100,000 bond.