The private service is to be held today at 9 a.m. PT at St. Martin's Episcopal Church.
Approximately 1,500 guests are expected to be in attendance.
Dr. Martin Murphy and his wife Ann Murphy, friends of the Bushes, paid their respects to Mrs. Bush by thanking her for her inspiration throughout the years.
"She was feisty, she was fun, and as soon as she embraced you, she made you family. Those were the three Fs," Dr. Martin said.
Barbara Bush touched so many lives through her charitable works over the years and inspired others.
That includes Jim "Mattress Mack" McIngvale, who, like so many many others, came out to honor and celebrate the life of Mrs. Bush.
"She's the First Lady of Texas, First Lady of Houston. There will always be a place in my heart and in houstonians for Barbara Bush," Mack said.
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