Prosecutors alleged during Harris' probable cause hearing on Thursday that the 33-year-old father sent explicit and pornographic text messages to several women, including a 17-year-old, on the day his son died.
Harris told police that he had forgotten to drop off his son, Cooper, at daycare in the morning and only realized what had happened on his way home from the office.
Last week, it was revealed that both Harris and his wife, Leanne, had researched information about animals dying in hot cars before Cooper's death.
Cobb County Police Detective Phil Stoddard also claimed at the hearing that Harris and his wife had taken out life insurance policies against their son. He also alleged that Harris lived a "second life" with "with alternate personalities and alternate personas."
Harris' attorney H. Maddox Kilgore maintained that he had simply forgotten about Cooper.
"Ross pulled out of a Chick-fil-A, and his mind went elsewhere. It's easy to get distracted when you get behind the wheel. Everyone does it," Kilgore said.