HOUSTON, Texas (KTRK) -- A medical examiner officially ruled an 8-year-old boy's death, who was found inside a hotel with "horrendous" injuries, a homicide.
In March, police and firefighters responded to a possible drowning call at the Quality Inn and Suites off the West Beltway around 11 p.m. However, investigators said it was obvious there was more to it. Police said Keyontae Holzendorf was found unresponsive with both new and old injuries, including patches of missing skin and deep ligature marks.
Detectives said 8-year-old Keyontae died the night of March 24, after being tortured by his mom and her common-law husband for months. As the investigation continued into the case, police said Kayla Holzendorf told them she and her common-law husband had sex while her son was dying.
Now, 24-year-old Kayla Holzendorf and her 28-year-old husband, Dominique Lewis, have been charged with injury to a child and tampering with evidence.
Harris County court records revealed the new details just hours after the child's maternal grandparents told ABC13 his mother concealed him from them before his death.
Sheryl Holzendorf, Keyontae's grandmother, traveled to Houston following the news of the boy's death and told ABC13 she had no idea about the abuse.
WATCH: Family of 8-year-old killed: 'We just want to know why'
"It's just shocking that this could happen to us," Sheryl said. "None of us knew what was going on because [Keyontae's mother] was so short on the phone, and every time that we would talk to her and Keyontae, she would have his face covered or we couldn't see his face at all. We could just hear him in the background, so we had no idea this was going on."
Sheryl said she and her family did not know Keyontae and his mother were staying at a hotel with her common-law husband.
WATCH: 8-year-old boy's parents charged in connection with his death
According to court records, the couple told investigators they "don't know what happened" to Keyontae. Police wrote they observed new and old injuries on his body the night he died and the details are graphic. They include burn patches on his chest and body, burns to the shaft of his penis, bruising to the left side of his forehead, a laceration to the left ear, small puncture wounds to different places and ligature marks on his ankles and wrists.
Kayla told investigators they sent Keyonate to the hotel room bathroom to take a bath while she and Lewis had sex. Afterward, when they checked on him, they found him unresponsive in the bathtub.
Sheryl said Kayla called her after the incident. She said the minute she heard the news, she and her family packed up and traveled to Houston. This included Sheryl, Kayla's father, Timothy Holzendorf, her stepmother, Ericka Holzendorf, and their children. They traveled from Florida and Georgia.
"I want everybody to know that Keyontae had a family," said Ericka. "We love him. He wasn't by himself, and he's not alone, and we're here to find out what happened ... we're here until we get justice."
The family has since set up a GoFundMe account to help give Keyontae a proper burial.
Kayla's next court date is scheduled for Dec. 8, while Lewis is scheduled for Nov. 30.