Jeffrey Dean Morgan and Hilarie Burton Talk Baby Son Gus, Parenthood: "It's Been Spectacular"

Exclusive! Supersecret couple open up about family during "date night" at Breaking Dawn premiere

Woo-hoo!

Jeffrey Dean Morgan and girlfriend Hilarie Burton are finally opening up about their baby boy, Gus.

The über-private couple secretly welcomed a son in March of 2010 after quietly dating for about a year and have since kept pretty hush-hush about their little bundle of joy.

Until now...

"He just said 'no' for the first time, which is f--ked up," Morgan, 45, told us at the Breaking Dawn: Part 1 premiere in L.A. "In one week it's just like, 'No, no, no!'"

What does 20-month-old Gus say "no" to most?

"Everything!" Burton, 29, said. "What's your favorite color? 'No!'"

"But everything is a first," Morgan said. "It's been spectacular."

As for parenthood, Morgan says life is "a lot of not sleeping, and then our one adult night we come here...this is our date. Can you believe it?"

Nothing says romance like thousands of screaming Twi-hards, right?

P.S.: Wondering why they were even at the premiere? They came to support their Twi-star friends, Billy Burke and Lee Pace.