A 3-year-old is fighting for his life after allegedly being shot in the head by his 6-year-old brother in their Philadelphia home.

WPVI reported that police arrested the kids’ father, Sirhaven Williams, 36, and charged him with endangering the welfare of a child and recklessly endangering another person following Saturday afternoon’s shooting. The father is facing criminal charges though the gun purportedly belongs to the children’s uncle, who also resides in the home.

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Police claimed that three brothers, ages 3, 6, and 12, were home alone at the time of the shooting. They believe the 6-year-old retrieved the gun from a second-floor bedroom and shot the toddler in the left side of his forehead, according to WCAU.

Neighbors reportedly heard the gunshot and called the children’s family. The 3-year-old was transported to a local hospital, where police said he remained in “very critical condition,” The Philadelphia Inquirer reported.

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“They shouldn’t have had access [to guns], no way,” neighbor Helen Williams told KYW-TV. “If they couldn’t secure it in the home, then when we left they should have took it with him.”

“No, it’s unbelievable and it’s unacceptable.”

CBS News reported that the 6-year-old and his parents are speaking with detectives. Investigators said they’re still trying to figure out how the child got ahold of the firearm.

[Featured Image: WPVI (screenshot)]