On the night of April 24, Roger Hepner, 56, was found shot to death in front of his home in the 1000 block of Addison Park Lane in the Northgate Crossing subdivision.
Hepner's son Mitchell took a shower and couldn't find his dad when he got out. So he went outside around 10 p.m.
"I saw blood. So immediately when I saw blood, (I applied) pressure, CPR," Mitchell told Eyewitness News.
Investigators say Hepner had just gotten home from the movies with his son when he went to get something from his truck. He was then confronted by at least one suspect, who shot him one time and fled.
He died from the gunshot wound.
Mitchell followed in his father's footsteps and joined the military.
He went out-of-state for training and had just returned back to Texas in mid-April. His dad had a surgery and he wanted to be close to help him.
Now Mitchell wears his father's dog tags in honor of a man who always served and protected others.
"I'll forever be grateful for things he taught me and how to live and how to be a good man," Mitchell said.
Mitchell and his sister Courtney Sondergaard spoke Wednesday morning during a press conference, where they pleaded for more information about their father's death.
They said it's been an incredibly difficult five months without him.
"I went to go call him once, and I wasn't able to do that," Sondergaard said.
His kids also said that he devoted his life to them and his grandchildren.
He had just met his second granddaughter before his death. She was born the morning he was killed.
"He didn't deserve this and we need answers. So we're here to ask people... he was always there for anybody that needed him. He needs you now. He needs answers, and so do we," Sondergaard said.
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Son of veteran killed in his own driveway: "I believe he was protecting me"