The 36-year-old television personality paid tribute to the former first lady in an Instagram post Tuesday following Bush's death. Hager is the daughter of Bush's son George W. Bush.
"I already miss this FORCE of a woman -- the 'enforcer' because she was the glue that held our family together," Hager captioned a throwback photo of herself with Bush and grandfather George H.W. Bush.
"She taught me to use my voice but also to value the opinions of others," she said. "She adored her friends and family; her loyalty was unwavering. Humor helps, she often said and it does, Gans, but I will miss your laugh terribly."
"She adored my Gampy, the first man she ever kissed; their love story is so engrained in the history of our family," the star added. "Thinking of my Gampy tonight -- no doubt missing his beloved desperately."
The "Today" host voiced her love for Bush, whom she said was also adored by the public.
"Gans, people stopped me all the time to tell my how much they loved you. I didn't mind sharing you with them. I love you more than tongue can tell, my Ganny," she said.
Bush died Tuesday at age 92 after turning down further medical treatment following a decline in health.
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