I don't accept the popular social media angle that an adult in the home set him up. Quite the opposite -- I think DR most likely confided about his dark feeling and desires to a faceless, internet acquaintance. He was confident enough in this person that he contacted them before he called 911.
By all accounts, DR has a good, supportive, relationship with is father and his maternal grandmother, and even his step-dad. I recall his step-dad was calling both his and his mother's phone while he was talking to the 911 operator. In fact, the only concern DR seemed to have was what was going to happen to his step-dad when he came home from GA, and whether or not he would be able to enter the apartment.
No concern for his motherless baby sister or his grandmother after he murdered his mom, her daughter.
Listening to the detective who attended the victim's autopsy testify during the 2-day hearing was the best wake up call for me. DR's attack was premeditated, forceful, violent, fearless, and fatal. No question in my mind that DR wanted her dead-- and DR had no intention for her to survive. MOO