"It's like a piece of me is gone. He was my identical twin brother," said Lance Spencer. "We've been inseparable since we were kids."
PHOTOS: Man dies in freak sand dune accident
Lonnie Spencer, 31, brought his five-year-old daughter to Spring Creek for a fun evening Tuesday. They'd come dozens of times before, and this time, there was plenty of sand to play with.
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Recent rains had forced sand from the bottom of the creek to build up along the banks, creating large dunes. So Spencer started digging, playfully building a tunnel for he and his daughter to sit in.
"Nobody would've ever suspected that you could have that much sand collapse," explained Dennis Johnston, the parks director for Harris County Precinct 4.
Spencer's daughter ran for help, but it was too late.
"He was my favorite person in the entire world," Lance said. "He was a piece of me. Without him, I'm not a whole me. He was a wonderful person. He always tried to make people laugh and smile."
He says his brother was a server at a Houston restaurant, but was pursuing a dream to become an environmental scientist.