Officers identified the victim as 28-year-old Manuel Rodriguez.
ABC13's Marla Carter spoke exclusively to Rodriguez's wife, Isamar Cruz-Sevilla. She said he died protecting her and their three children.
Video: Wife says husband was hero for protecting her family
Man shot and killed protecting his family
"There was a man just waiting for us and then he just started shooting at my husband, and then he tried to shoot at my babies too. He tried to open the door," she said.
She said they had returned home from a trip around 8 p.m. Sunday when they were approached by a man.
Officers said the suspect demanded items from Rodriguez and shot him. Rodriguez fired back. Both men died.
Cruz-Sevilla has a message to anyone who ever things about firing a gun.
"They need to think before they do this stuff because he had a family. Then he took him away from us. That's cruel," she said.
ORIGINAL REPORT: Two shot and killed in SW Houston
Two men dead at SW Houston apartment
Cruz-Sevilla said right now her husband, their hero, is still watching over them from above.
"Maybe in heaven (he is) watching us," she said.
Rodriguez leaves behind a wife, a 1-year-old, 2-year-old and 8-year-old. The couple was married for 9 years.
Police have not released the name of the suspect at this time.
Police: Kids watch as father murdered in SW Houston