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"Thank you for all the lovely thoughtful and heartfelt birthday wishes for our little king! ❤️🙏🏽," the mother of two captioned a photo of her son holding a car-topped cupcake.
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Both Alfonso Ribeiro and his wife Angela used Instagram to wish The Fresh Prince of Bel-Air alum's daughter Sienna a happy 15th birthday on Oct. 7.
"Happy Birthday to my incredible sweet talented smart gorgeous daughter Sienna. 15 today. Why can't they stay 5?" the proud dad wrote alongside a snap of the birthday girl.
Wrote Angela in a lengthy caption accompanying a photo gallery of Sienna over the years, "I couldn’t be more proud of the young woman you are and becoming."
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"Watch out this one might just rule the world or become a Unicorn Slayer 🦄 ha ha," added the mother of four. "Whatever she does I am beyond proud to be her mom!"
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Parents of two Olivia Wilde and Jason Sudeikis don't share a ton of photos of their children, but each glimpse is more adorable than the last — including this snap Wilde posted of daughter Daisy Josephine on her first birthday (Oct. 11).
"We dream of a time when you won't have to apologize for your brilliance, or sacrifice your self-respect to prove your worthiness," the actress wrote.
She continued, "This world is yours, kiddo. We're just the cleanup crew. I love you. Happy birthday. ❤ #internationaldayofthegirl"
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HARPER AND GIDEON BURTKA-HARRIS
The Burtka-Harris twins are 7! Halloween pros and pint-size jet-setters Harper Grace and Gideon Scott celebrated their big day on Oct. 12 with lots of love from their dads Neil Patrick Harris and David Burtka on Instagram.
"I'm so grateful to have these two in my life, so fortunate to watch them grow," Harris captioned an adorable outdoor snap of the pair. "They have increased my happiness by a factor of twin! #grateful #happybirthday"
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The older son of Alicia Keys and Kaseem "Swizz Beatz" Dean, Egypt Daoud, also turns 7 this month.
"STILL speechless about everything you are and everything you're becoming!!" the singer captioned an Oct. 14 video montage set to her hit "Speechless."
"Happy 7th birthday to one of my best creations YET!!!" Keys added. "The most beautiful song I've ever heard!! 😍😍😍"
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Another first birthday on Oct. 19? Major James! Kyle and Eva Amurri Martino's younger child will most likely be heavily doted on by his parents, 3-year-old sister Marlowe Mae and grandmother (er, "Honey") Susan Sarandon.
"Welp. He's officially feeding himself. No need for Mom anymore! 😱😭✨🎉🥄 ," Amurri Martino captioned an Oct. 5 video of Major digging in to his dinner.
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"[Jovan] is younger, so he either doesn't understand or maybe he just doesn't care," Oz joked of her son's opinion on her pregnancy to Fit Pregnancy and Baby for their November cover story.
She added of Jovan, whose birthday is Oct. 21, "He's such a dude."
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ALFONSO "AJ" RIBERIO
"Love playing 9 holes of golf with AJ," Riberio captioned a photo of the father-son duo earlier this year.
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