NORTH TEXAS (CBSDFW.COM) – CBS 11 has learned a fifth child in North Texas was shot this weekend in four separate shooting cases, that included the death of a 4-year-old boy in Fort Worth.

A 14-year-old girl received treatment at Cook Children’s Hospital in Fort Worth after being transported there from a Burleson medical facility early Sunday morning.

On Monday, Child Protective Services said it’s investigating the accidental shooting in Fort Worth and two others in Arlington.

A CPS spokeswoman says it has not removed any children from the three homes.

In Fort Worth, police say criminal charges will not be filed against the parents of the 4-year-old boy who died after being shot by his 5-year-old brother.

A 2-year-old boy was in the home at the time but not hurt.

The CPS spokeswoman says the agency has previously visited the home, but couldn’t provide more information.

Police wouldn’t disclose any information about the gun or other details.

In Arlington, police say the 6-year-old boy who was shot in the head remains in very grave condition.

Authorities say they believe the victim’s ten or eleven year old brother shot him.

A three year old sister, police say, may have been grazed by a bullet.

Police say the 10 or 11-year-old is non-verbal, and that an older brother, perhaps 16, told them he bought the weapon used – a 22-caliber rifle.

According to investigators, the parents said they didn’t know anything about the gun.

In another case being investigated by Arlington Police, an eight year old girl shot in the buttocks continues to recover.

Police say the family told them that the weapon, a nine millimeter semi-automatic Uzi-Mach 10, fired after she sat on it.

Authorities say the weapon was reported stolen in Bastrop near Austin.

Lt. Christopher Cook of the Arlington Police Department says the shooting of the 6-year-old boy was difficult for officers to face.

“I heard the radio traffic of the officers there. They were screaming for EMS to get there as fast as they could because as any first responder, your heart goes out. You have a child shot in the head, so it’s tough,” Lt. Cook said.

The ATF is assisting Arlington Police with the investigation to trace the guns.

Lt. Cook said they have not filed any criminal charges in their two separate cases but their investigations are continuing.