Muskegon County deputies and child protective services are investigating the shooting of a four-month-old girl. Investigators say it was the baby's two-year-old brother who fired the gun.

It happened Thursday night at a home on Calumet Avenue, in the Lakewood Club community.

The Muskegon County Sheriff says the two-year-old boy found a rifle lying on the ground in a bedroom closet. The Sheriff says the boy began playing with the gun and fired six shots, with one round hitting his baby sister.

Neighbors say they've heard the sound of shots fired coming from outside the house in the past.

"I've heard pellet guns being shot out the back door and I think maybe they're practicing," says Pamela Sprague, a neighbor.

However, she didn't think there would be gunshots coming from inside the home.

"We thought somebody had shot at the house but then when they were investigating they said it came from inside," says Sprague. "It's like well, that's a little different."

Investigators determined a two-year-old boy got his hands on a .22-caliber rifle. They say one of six rounds grazed his four-month-old sister's arm who was lying on the bed at the time.

"Sad that the little girl got hit like that, something they have to look into get it straightened out," says Sprague.

The mother and grandmother were home at the time, according to the Sheriff. Sprague says the children's father also lives there.

"Should haven't had guns laying around for sure, have them put up when you have kids around," says Sprague.

Fortunately, on Friday we learned that baby girl had been treated and released from the hospital. She's expected to make a full recovery.

The Sheriff says they've concluded their investigation and forwarded the case to the prosecutor for possible child endangerment charges.

The Sheriff says the incident underscores the dangers of having a loaded weapon in the home that is not secured. He urges gun owners to follow all safety recommendations, including to never have a loaded weapon unsecured and within reach of children.