HOUSTON, Texas (KTRK) -- The search is on for a suspect who shot and killed a family dog during a home invasion.At 4:45 Wednesday morning, Sara Garza's daughter walked to her car to drive to work, something she does every morning. As she pulled on her seat belt, there was a knock at the window; she turned to see a young man pointing a gun at her. He forced her to get out of the car, and take him inside the home that she shares with her parents and two other siblings."When I peeked through the mini blind I saw the guy behind her with the gun at her neck," said Garza, who was inside when her daughter came to the door with the robber. "I opened the door and all he said was, 'I want money, give me the money.' We have no money. I don't know what he wanted."The robber managed to get a purse and a wallet, but before leaving, he turned and did something unthinkable. He shot the family dog, Tita, who was standing by the door."My mother died two years ago, and she left me that dog, to take care of," said Garza through her tears. "She's really close to us. She's a good dog."Stunned that a robber would shoot the family dog for no reason, the Garzas chased after him. Surveillance video shows the robber leaving, with Garza, her husband Ramiro, and two kids running behind.Ramiro Garza then jumps in his truck, and chases the suspect."I tried to catch him," Garza said. "I was running 70, 75 miles per hour to try to catch him. I couldn't catch him, there was no way."The family also called 911. The Harris County Sheriff's Department is now investigating.Fortunately, every moment outside the home was captured by surveillance video and the suspect's face is plainly visible.The Garzas said the robber is around 22-24 years old, and driving a light colored Malibu. Their hope now is that someone will recognize the man in the video and call authorities."I hope somebody recognizes him and turns him in."