We spoke with the suspect's boyfriend, who was the first to call police to get the boy some help.
Arturo Harmon remembers finding his girlfriend's baby boy convulsing early Saturday morning.
"I had the little boy just like this in my arms, and he was shaking, and I couldn't control it," Harmon said.
Harmon had just returned to his spare apartment in the 800 block of Richey where he found 23-year-old Juanicia Alfreda Edwards asleep in one corner and her 22-month-old baby boy in serious trouble on a couch cushion.
He scrambled to get his neighbor, Milton Harris, for help.
"I held him and had him in a blanket until the ambulance came, pouring down rain," Harris said.
The toddler was rushed to the hospital and it wasn't long until Pasadena police pieced together what they believe happened. According to investigators, it appears Edwards shook the child to stop his crying.
Edwards was charged with injury to a child for allegedly shaking her son. Neighbors say he showed signs of abuse that morning.
"He had bruises on his chest, and his head was so swollen, and it was like she beat him bad," Harris said.
Harmon, a part-time chef, said he only began dating Edwards a few weeks ago. He let the mom and her son move in with him in part, he says, because she needed help.
Looking back, he said now wishes he would have done something more.
"Do you regret not calling child services, or CPS earlier?" we asked.
"Yes, I do," he said. "Look at the situation now. I didn't think it would come to this."
The child was in critical condition Monday due to a brain hemorrhage.
Edwards was being held Monday at Harris County Jail on $50,000 bond.