A Texas man shot dead by his neighbor who mistook him for an intruder was really sleepwalking, the victim's family told WFAA-TV.

On Dec. 26, Wise County deputies responded to a 911 call from a Rhome homeowner saying a man, identified as Spencer Crandall, was trying to break into his home. The homeowner was drawn outside after Crandall began knocking and ringing the doorbell at around 4 a.m., county sheriff David Walker said.

Once the homeowner was outside, a struggle ensued. The homeowner told Crandall he was armed, but when Crandall kept saying he had to get into the house, he shot the 31-year-old in the chest, Walker said. His body was found on the front porch.

As investigators piece together what happened the morning Crandall died, his grieving family is speaking out to fill in the blanks.

"He had been sleepwalking," Ryan Crandall, the victim's brother, told WFAA. He said his brother's wife would sometimes have to stop him before he left the house.

"Sometimes he would make it into the front yard, and she would go out and physically grab his arm and pull him back into the house so that he would be safe," Ryan told the station.

Spencer's family said the sleepwalking was getting worse, most likely due to the medication he had been prescribed for ruptured discs in his back. The pain was particularly bad on Christmas Eve, his brother said.

"Perhaps he drank some beer on top of the medicine, something he would not normally have done because he was a Mormon, and the faith forbids alcohol," Ryan said.

"He would only have obtained it for the purpose of dealing with his back pain."

The next night, Spencer's wife Amanda was not home to stop him from leaving. She was away visiting family, according to the brother.

Spencer was not armed when he arrived at his neighbor's home, police told station. He was arrested for criminal trespassing in 2012, but his brother says it was because he drove past a traffic barrier where he attended college at the University of North Texas in Denton.

An autopsy will be conducted to to determine if Spencer had drugs or alcohol in his system, WFAA reported.

A grand jury will most likely decide if the homeowner, Craig Rigtrup, should be charged. But police said it appears he was doing all he could to protect his family.