It happened around 1 a.m. at a home on the 1800 block of Horace Avenue in Abington Township.
Officers were called to the scene for reports of a man who had been shot during a home invasion.
Investigators say the woman who lived at the home was returning from a local casino when the incident took place.
The woman told police that the suspect, identified as Khabir Shepard, pointed a gun at her and forced his way inside.
Shepard allegedly pushed her to the ground and took her purse from the dining room table.
That's when the victim reportedly screamed for help from her adult son, who was asleep in the back bedroom.
Police say the son, who had a legally owned firearm, ran to his mother's aid.
When the son got to his mother, he reportedly saw a gun in Shepard's hands and shot twice, police say.
Shepard was struck in the back and arm, and police say as he tried to escape, he collapsed on the front lawn.
Abington police later took him into custody. Officers said a handgun was recovered in front of the home, and investigators believe it was the weapon Shepard used during the incident.
Investigators later said that Shepard had followed the victim home from the casino she had been at.
Shepard has since been charged with robbery, aggravated assault, burglary, and carrying a firearm without a license.