Jenna Bush Hager has celebrated her daughter's sixth birthday with a series of super adorable vacation photos.The TODAY host welcomed her daughter Poppy in 2015 and took to Instagram to pay tribute to her middle child."Happiest birthday to the sparkliest, fire-cracker, fierce and feisty six-year-old," she captioned the post. "You came into this world with a roar and have added an effervescence to our family ever since.