Pharr police said a 22-year-old shot his sister TMs boyfriend on Saturday morning.
Police responded to a home on the 500 block of Golden Drive at around 6:35 a.m.
When they arrived, officers learned that 18-year-old David Reyes had been shot with a shot gun.
Police said the teen was shot by his girlfriend TMs brother, 22-year-old Derek De La Rosa.
Reyes sustained injuries to his face.
The teen was taken to McAllen Medical Hospital to be treated for his injuries.
He was air lifted to a San Antonio hospital and is listed in stable but critical condition.
De La Rosa was taken into custody and charged with Aggravated Assault with a Deadly Weapon.
His bond was set at $100,000 and was transported to the Hidalgo County Sheriff Office.