Neil Patrick Harris & David Burtka Share the Cutest Pics of Harper & Gideon On Their 4th Birthday!

Neil Patrick Harris and David Burtka shared two adorable pictures of their twins Gideon and Harper on their fourth birthday!

“Happy 4th birthday, Gideon and Harper. I can’t believer that you used to be tiny baby things. And now, this.” the 41-year-old Gone Girl actor wrote on his Twitter account, along with the photo.

“Today is an exciting day!! Our twins turn 4! I can not believe how old they are! #solucky #happybirthday!” David wrote on his Twitter.

Happy birthday, Gideon and Harper – they look like they are all grown-up!