The Houston Police Department says Joseph Guillen was crossing Westheimer between South Gessner and Tanglewilde when a car hit him just after 4 a.m.
The driver never stopped, and no one could get a description of the vehicle that hit him.
RELATED: Driver takes off after fatally hitting man who was trying to cross street in SW Houston, HPD says
Guillen's sister, Estella, spoke to ABC13 about her brother. She said he loved writing poetry, doing woodworking, and exploring.
"He liked to travel. He liked to be out and about," Estella Guillen said.
The last six weeks have been an absolute mystery to her family regarding her brother's death.
They're urging possible witnesses, as well as the hit-and-run driver, to come forward.
SEE HERE: Only 20% of hit-and-runs are investigated in Houston, fewer are solved, data shows
Only 20% of hit-and-runs investigated in Houston, fewer are solved
"Closure is part of the grieving process, and it's hard to have it when you don't know. There are so many unknowns," Joseph's sister said.
To be eligible for the reward, tips must be called in to Crime Stoppers directly at 713-222-TIPS. (8477).
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