"Everyone says that it's such a blur after it happens," Neil told People, of becoming parents to Harper Grace and Gideon Scott, born October 12 via surrogate. "I find myself constantly just trying to wrap my mind around it."
David, Neil's 35-year-old longtime love, said that holding their newborns in the delivery room was "just absolute joy."
"Harper has been fussy but Gideon is the easiest baby in the world," David told the mag. "They're just now starting to recognize us and smile."
The happy family recently moved into "more kid-friendly" digs in the Hollywood Hills, furnishing the twins' new nursery with an "old-school Disney theme park" look, according to the mag.
"I just love the way [the twins] smell. And we can use them as an excuse to get out of almost anything," Neil added, jokingly. "That's cleared the calendar in a good way."
As previously reported on AccessHollywood.com, the "How I Met Your Mother" star announced the babies' arrival in October via Tweet, writing, "Babies!! On 10/12, Gideon Scott and Harper Grace entered the Burtka-Harris fold."
"All of us are happy, healthy, tired," the Emmy winner continued in his Tweet. "And a little pukey."
In August, Neil first announced that he and David were expecting twins through Twitter.
"So, get this: David and I are expecting twins this fall," Neil Tweeted at the time. "We're super excited/nervous/thrilled. Hoping the press can respect our privacy…"
David has experience with twins; he helped to raise twins from a relationship with a previous boyfriend, although he wasn't a primary parent to them.
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