Neil Patrick Harris' Twins Turn 1

10/12/2011 05:42 pm ET | Updated Dec 12, 2011

Happy birthday, Harper Grace and Gideon Scott!

Neil Patrick Harris and David Burtka's twins celebrated their first birthday Wednesday and the "How I Met Your Mother" star tweeted a shout-out to his adorable kids and partner.

"Things I dig: our twins Gideon and Harper, who are one year old today! They are glorious. So proud to be their Papa," he wrote, adding, "And I'm in awe of, and so grateful for, @davidburtka. He is, in my humble opinion, the greatest dad in the history of ever."

Harris and Burtka announced they were expecting twins via surrogate in August 2010 over Twitter, and then shared the news of their birth last October.

"Babies!! On 10/12, Gideon Scott and Harper Grace entered the Burtka-Harris fold. All of us are happy, healthy, tired, and a little pukey," Harris tweeted.

Since then, we've seen tidbits of Harris, Burtka and the twins -- including photos of the family hanging out with Elton John on his yacht -- but our favorite photos of the twins come from Harris' appearance on "Late Show With David Letterman," where he showed off holiday-themed photos of the kiddos.

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