NORCROSS, Ga. -- On Saturday morning, Daniel Vick stopped by to drop off flowers and pray in front of the family's Norcross home.

Less than 24 hours before the home in the 700 block of Pebble Creek Drive was surrounded by crime scene tape. Gwinnett County Police Corporal Deon Washington said on Friday afternoon a father came home to find his family dead in what detectives believe could have been a murder-suicide.

Police arrived at the home after receiving a "person shot" call around 4 p.m. The call came from the father who told police his 55-year-old wife, 26-year-old son and 10-year-old daughter were shot to death.

As police investigate the shooting, they believe the son might have killed his mother and sister before turning the gun on himself.

Attached to the flowers Vick dropped off was a handwritten note for the father.

"I left a note, letting them know they can call us and that the community is standing behind them," Vick told 11Alive's Joe Henke. "I wanted to leave them something to let them know the aren't alone."

As of Saturday afternoon, the medical examiner's office has yet to release the official cause of death. Washington said he doesn't know of previous domestic issued inside the home. His department's detectives are now working to determine why the shooting happened.

"Detectives are working to determine the sequence of events that took place before the homicides and during and more importantly why," Washington said.

PHOTOS | Police investigate fatal Norcross shooting

Shortly after Vick left, another neighbor dropped off a card outside the home. She said the small gesture was the least she could do.

"We try to process it right, as neighbors," Miaya Johnson said. "But I can't imagine what the family is going through."

From the outside both Vick and Johnson said the family seemed happy and were great neighbors. "They seemed fine, the mom was a wonderful loving mother," Vick said.

Johnson said the possibility of the son being responsible for the shooting is shocking.

"He would walk his sister to the bus some mornings," Johnson recalled. "He would walk his dog, go running with him around the neighborhood. Just super nice, super friendly, I can't even imagine that if he did that, I can't image that."

Vick said with Thanksgiving and Christmas approaching, he hopes more people will reach out to the father and his extended family to offer their support.

11Alive is working to gather details on this developing story. Check back for updates as they become available.

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