HOUSTON -

A $70,000 reward combined with statewide pleas for information in the murder of a family of four in Cypress has still not given Harris County sheriff’s deputies enough information to arrest anyone in the seven-week-old case.

The family’s two cars still sit in the driveway. Automatic lights turn on each evening and a lawn service keeps the yard manicured, neighbors tell Local 2 Investigates.

Sheriff’s deputies found Maoye Sun, 50, his wife, Mei Xie, 49, and their sons, Timothy, 9, and Titus, 7, dead in their home in at 14015 Fosters Creek Drive Jan 30 in northwest Harris County. The medical examiner said each died of a gunshot wound to the head. Timothy was also shot in the torso.

“Those two little boys had the biggest light in their eyes,” neighbor Tiffany Bever said. “They were sweet. They loved everybody here. They rode their bikes with their friends and went to taekwondo.”

Investigators say they narrowed the time frame of the murders to between 7 p.m., Jan. 24 and 11 a.m., Jan. 25.

“I still cannot understand why someone would want to take the lives of two children,” Harris County Sheriff Adrian Garcia said Feb. 19. “Evil has occurred and investigators are working to confront them and bring them to justice.”

QUESTIONS PERSIST

Many questions remain, including why someone would kill the family.

The family members lay dead in their home for days before a friend asked police to check on the family. That’s when police discovered the four bodies inside the home.

“What’s the reason behind this? What’s the motivation,” Garcia asked at a news conference after the incident.

Crime Stoppers is offering the reward for information that helps investigators bring the suspect or suspects to justice. Deputies have reached out to the public for tips. They’ve asked Houston’s Chinese TV station to broadcast stories about the incident. Billboards have gone up in cities statewide.

Though there has been considerable effort to track down the killer, no one has been arrested yet.

“I don’t know of a police officer or a detective anywhere in the world who wouldn’t be working as hard as they could to try and solve this case,” former Houston Police investigator Mark Stephens told Local 2 investigative reporter Jace Larson. Stephens, who now runs his own private investigative firm, has not been briefed on the case.

Stephens says detectives almost certainly have more information than they are releasing. There’s good reason for that to be the case, he said.

"You don't want to put yourself in a position where the bad guy could use your information to create an alibi," he said.

Sometimes he says criminals behind bars lie and use information they saw or read hoping to get their sentence reduced.

"They might think, ‘This is my ticket out. All I have to do is get all of the information I can and pretend that I know who did it. All of a sudden all of the attention is on me and I have a chance to get out,’" Stephens said.

By using details of the crime only known to investigators and those involved in the crime, deputies have an easier time vetting real tips.

Stephens thinks the crime could likely be solved by someone getting arrested for an unrelated crime.

"It's going to take someone who was there or who has knowledge of it, probably getting arrested for something else and wanting to cut a deal," Stephens said.

SEND POLICE A TIP

If you have a tip about the killings, call Crime Stoppers at 713-222-TIPS. You can also text your tip. Send TIP610 plus your tip to CRIMES (274637)

Have an investigative idea for reporter Jace Larson? Email him at jlarson@kprc.com or send him a message on Facebook at facebook.com/jacelarsontv or Twitter at twitter.com/jacelarson.