The Today star marked her co-anchor's milestone day with a touching tribute on Instagram that left fans reaching for a box of tissues. She penned: "My sister-wife, devoted friend, litigator of all things literally, dog-sweater-wearing, enthusiastic partier until 9pm turns 5-0 today."
WATCH: Today's Jenna Bush Hager's video with Savannah Guthrie leaves some fans horrified
She added: "@savannahguthrie deserves to be celebrated for her dedication to her family and friends, her loyal heart, and her relentless faith. Sometimes life surprises you with a dear friend who loves you for all of you—what a wonder it is to be in your glow SG!"
Among the gallery of photos of the pair sharing laughs both on and off the air was a throwback snap of Jenna and Savannah each modeling a pixie hairstyle while wearing high-waisted denim jeans – and they looked almost unrecognizable.
Another cute throwback pic saw Savannah and Jenna posing with Savannah's daughter, Vale, now seven, and son, Charley, five, and Jenna's two oldest kids, daughters Mila, now eight, and Poppy, now six.
Jenna and Savannah look so different with short hair
And another snap that highlighted their close bond saw Savannah cradling Jenna's newborn son Hal, now two, in the hospital following his birth in August 2019.
Fans were blown away by Jenna's touching words, with one responding: "One of the nicest friend tributes I've ever read." A second said: "Happy Birthday to SG! I love how close you all are on Today."
Jenna delighted fans with her incredible photos highlighting her close bond with Savannah Guthrie
A third added: "Beautiful words." Another loved the image of Jenna and Savannah rocking their short hairstyles, commenting: "Absolutely nothing beats photo number 4."
Jenna wasn't the only star to pay tribute to Savannah. Hoda Kotb also sent her birthday wishes alongside a smiling photo of the pair on the cover of Fly Washington magazine.
"Happy 50th my sweet. Love to see you soar," Hoda wrote in her caption.
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