WINDSOR MILL, Md. (WJZ) — Baltimore County police detectives are investigating how a 22-month-old girl was injured Sunday night during a domestic shooting.

According to police, the domestic shooting happened on Derby Shire Circle around 7 p.m. Sunday night. Police said the shooting stemmed from an argument between the child’s mother and an ex-boyfriend. The man allegedly assaulted the mother when he went to the home to pick up some items.

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Nicole Smith, the 22-month-old’s grandmother, told WJZ her daughter — the girl’s mother — is five months pregnant and the ex-boyfriend is the unborn child’s father.

Child Injured In Possible Domestic-Related Shooting In Windsor Mill, Police Say

When the couple began to argue, the disagreement got physical, at which point Smith’s son jumped in to help.

“He was trying to get him off of his sister because, you know, she’s five months pregnant,” Smith said.

During the assault, the suspect pulled a handgun. A struggle ensued and Smith’s son was struck with the gun in the upper body. The gun discharged during the struggle leaving the toddler with a graze wound.

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Baby Promise. Photo contributed.

The suspect left the gun at the scene, police said, then fled the home. He was later arrested by responding officers after a brief foot pursuit.

The 22-month-old named Promise has since been discharged from the hospital. Her mother remains there for treatment.

“My granddaughter had to get like five or six stitches,” Smith said.

The family isn’t a stranger to gun violence.

“I lost my 16-year-old son four years ago to the streets,” Smith said.

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The suspect’s identity was released Tuesday after charges were announced.

Annie Rose Ramos