Neil Patrick Harris and David Burtka Celebrate Their ‘Amazeballs’ Twins as They Turn 14: ‘Becoming the Best Humans’

Neil Patrick Harris and David Burtka’s twins are growing up!

On Saturday, Oct. 12, the How I Met Your Mother alum, 51, shared a sweet Instagram tribute for his twins Harper Grace and Gideon Scott on their 14th birthday, describing them as “amazeballs” as he praised them both.

“Harper and Gideon turn 14 today,” Harris began the caption of his post, adding that he has “never been more proud of anything in my entire life, and I suspect I never will.”

He then described how he and his husband, 49, both “marvel at their maturity, are wowed by their warmth, chuffed by their charm. We love them both unconditionally, and their hugs fill us with life.”

“We don’t say any of this to them, obvs, or they’d recoil or leverage it to their advantage. But they’re not on Insta, so I’m free to speak honestly. They’ll never find out,” the proud dad playfully added.

“Happy Birthday, Harper and Gideon. You’re both amazeballs,” Harris concluded his sweet message.

Harris included a sweet photo of the twins — whom he and Burtka welcomed via surrogate in 2010 — with his birthday shoutout. The image showed the two sitting in a lounge with a display of balloons behind them.

Burtka also shared a special birthday tribute to the twins on his own Instagram account, alongside a carousel of black-and-white photographs that featured himself, Harris, Harper and Gideon.

“Happy 14th Birthday to our incredible kid[s],” he began.

“They are becoming the best humans. I am so proud to be their dad. Although teenage years are tough, they are managing it splendidly. I have witnessed- if you put the work in you get it back,” Burtka continued, before taking a moment to look into the future of his kids’ lives.

“I can’t wait to see what the next years have in store- however, I am holding on to all the little moments when they still want to connect. #luckydads,” he concluded.

The proud parents — who first started dating in 2004 and married in Italy in 2014 — regularly share updates on life with their twins on social media.

Back in June, Harris posted some throwback snaps from a family trip to France for Spring Break.

“#tbt to Spring Break in Cognac, France. An unforgettable week of family memories. Eternally grateful to Le Logis for inviting us into their home. Ah, I miss it. #grateful @dbelicious @lelogiscognac @forbestravelguide,” he wrote alongside a carousel of images of the family enjoying their trip.

The sweet photos included shots of Harris, Burtka and the twins posing in front of French buildings, riding bikes and playing a game.

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The couple spoke to PEOPLE in February about parenting teens, with Harris revealing how “great” the then 13-year-olds were and how “proud” he is of them.

“They’ve been great,” he told PEOPLE at the time. “They’re surprisingly great. They’re city kids, they live in Manhattan, New York, so I find them fairly mature 13-year-olds, but it’s nice to see them navigate the world now that they’re teenagers with some sense of knowledge and sense of self.”

“That’s what we work really hard as parents to do is instill some sort of values into them, and then you sort of let them go and exist and they’re crushing it. Very proud of them,” he continued.

However, the star said that the Burtka-Harris household isn’t yet the place where their teens and their friends hang out.

“Honestly, they’re at such a rigorous school. Literally they come home and do homework. It’s wild. Not a hangout house yet. I mean there are play dates and sleepovers and things like that, but maybe soon,” Burtka said at the time.

He added, “We’re definitely told we’re the coolest parents out of all the friend groups,” while Harris teased that he “didn’t realize it was a competition!”