The Harris County Precinct 4 Constable's Office responded to reports of a shooting in the 8600 block of Cedar Walk Drive around 7:30 a.m.
Surveillance video shows the suspect walking up to the woman, who was setting up for a garage sale in her driveway and shooting her four times. The shooter then turns and runs off to a vehicle and drives away.
Neighbor Candy Ellis heard the gunshots and called 911.
"Three gunshots, rapid-fire, then wait another second or two, and then another gunshot," said Ellis.
Detectives are closely examining the video in hopes of determining the type of truck the shooter was in.
"Video is always important. It certainly gives us a starting point," said Lt. Jeff Stauber, Harris County Sheriff's Office.
Friends and loved ones can't understand why anyone would do this. The 29-year-old victim's mother-in-law was in shock.
"They just live normal lives. They are working and they're good people," said Margarita Barraza, the victim's mother-in-law.
"Very cordial people, very, very nice, said hi all the time, one of those kind of things. Kind of shocked. I'm still trying to process all of it," said Cindy Ghrist, a neighbor.
The victim volunteered for a group that works with Make-A-Wish. Make-A-Wish says they're shocked and saddened by the news.
The video also shows the victim's husband leaving the home around 6:48 a.m. and the shooter's truck pulling up at 6:52 a.m.
Investigators say the suspect drove away in a black truck.
The victim was transported to Memorial Hermann Hospital by Life Flight. Authorities say she's in critical condition.
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