The father of a 12-year-old boy arrested in the stabbing death of his 8-year-old sister, Leila Fowler, said he supports his son and believes he is innocent until evidence proves otherwise.

Barney Fowler told The Associated Press today that his family is standing behind the boy "until they have the proper evidence to show it's my son."

On April 27, Leila's 12-year-old brother, who has not been identified because he is a minor, told Valley Springs, Calif., authorities he found his sister stabbed to death after an intruder broke into their home.

The 12-year-old said he called his parents, who alerted sheriff's deputies. The boy told authorities the intruder, who he described as a tall man with a muscular build, fled the scene. The boy's description launched a 15-day manhunt that included door-to-door searches and divers in a reservoir.

The Calaveras County Sheriff's Office in Northern California announced the arrest of the 12-year-old boy late Saturday. He is expected to be charged with homicide.

Neighbors in Valley Springs, Calif., where the family lives, said they feared all along that Leila's brother -- not a mystery man the boy described -- might be responsible for the girl's stabbing death. Community members were both relieved and saddened by the news of the boy's arrest.

"It made us sadder, because he's just 12 years old," Barron told ABCNews.com. "The family has lost two children now."Barbara Barron, who lives two doors down from Leila Fowler's home, said she suspected the brother from the beginning and found it unusual that he allegedly called his parents before calling police when he found his sister.

She described the neighborhood as "really quiet" and "very somber."

"Everybody speculates, and everybody said this and that, but I just prayed," Mary Gallagher, a friend of the Fowler grandparents, told ABC News' Sacramento affiliate KXTV. "I prayed it wasn't him."

Neighbors said they had not seen Leila's family since her death, but Leila's grandfather said the family is struggling.

"I don't know what to think. They had been trying to make a case for a while now," grandfather Dennis Fowler told KXTV. "It's been really hard on the family."

Several knives were taken from the Fowlers' home to determine if one of them had been used in the murder, The Associated Press reported. In the days after the stabbing, a neighbor, who told police she saw a man flee the home, also recanted her story, the AP reported.

Authorities initially said Leila's brother was not a suspect, but acknowledged they were continuing to talk with him.

"We are continuing to talk to him, which would be normal because he was the last person with the child," Calaveras County Sheriff's Capt. Jim Macedo said at a news conference last month.

Macedo said at the news conference that investigators had collected fingerprints and what they believed to be DNA at the crime scene.

Authorities have not said what led to the arrest the 12-year-old boy on Saturday.

After a tense two weeks, Calaveras County Sheriff Gary Kuntz said he hoped the arrest would bring some peace of mind to a community that has been on edge.

"Citizens of Calaveras County, you can sleep a little better tonight," he said.