Cox told detectives she picked her son up from her boyfriend's house around 2 p.m. that afternoon and the paperwork shows she told police that's when the baby was hurt.
But after investigating, the criminal complaint shows officers uncovered text messages that made it clear that she picked up her son earlier that morning.
They also found pictures she posted photos on Facebook from that day and in those photos, the baby didn't have any visible injuries.
The criminal complaint shows that a doctor told officers the injuries to the baby's abdomen and genital area were caused by blunt force trauma and the baby never could have caused those injuries himself.
And as for the bruises on the baby's face, court papers show a doctor concluded they were caused by some sort of object.
It may not have been the first time something like this happened. The criminal complaint shows officers searched Cox's phone and found photos dated from a month before where her baby boy had similar injuries to his abdomen. Doctors say there's no way the 7-month-old baby could have caused them himself.