Paramedics tried CPR to revive the newborn baby but the boy died a short time later.
Alexander was taken into custody two hours later after she was found involved in a car wreck about 20 miles away.
She was arrested and jailed on a murder charge pending a court hearing Tuesday.
Alexander's family made excuses for her saying she was having a rough time, dealing with an abusive boyfriend and while joyous, her son's birth made things tougher.
Her mum, Sandra Jones said:
"She loved that baby with everything she had in her. I think she felt like she just couldn't do it herself,"Jones said, Alexander had taken maternity leave from her job at McDonald's to recover from her cesarean section, and was nervous about returning to work. She said her daughter was intensely private and proud, pushing away offers to watch the baby or to get her other help. Jones said she only discovered after her daughter's arrest that Alexander was being seen for depression before and after giving birth.
Alexander had hoped her boyfriend of a year-and-a-half would have been more supportive after she got pregnant, but instead he moved her to a filthy home 20 miles from her family and went back to doing drugs and abusing her.