Police said that in the videos, she is screaming that Grant had been beating her for four years.
"It broke my heart. It just, it's something you don't think when you just talked to your son," said Geraldine Grant Bryson, Grant's mother.
Grant Bryson is still mourning over the murder of her son but she is thankful he followed her advice to start recording on his phone when he was in trouble.
"(I told him) get the video, record it and lay the phone down," she said.
Grant did just that and recorded his own murder. Harp told police she shot him in self-defense.
Police spent weeks trying to get evidence from Grant's phone, with no luck. But when they spoke to Harp about a medical release, they were able to get the footage.
"It's unbelievable. There is no way anybody would believe this," said Grant Bryson's attorney, Sean Joyner.
Officers said that, in the recording, Harp shoots Grant and he pleads for water and expresses a desire to hug his daughter.
Grant Bryson said all she wants is justice.
"I just want her to realize that you just don't go around killing people," she said.