Less than two months after the birth of their son, Axl Jack, Josh Duhamel and Fergie are already thinking about baby No. 2 Credit: Michael Buckner/Getty

No time to waste! Josh Duhamel and Fergie's son, Axl Jack, isn't even 2 months old -- but the Transformers actor already has more babies on the brain. Asked about his bundle of joy at the Salvatore Ferragamo-sponsored Wallis Annenberg Center for the Performing Arts Gala in Beverly Hills on Thursday, Oct. 17, the new dad revealed plans for more just like little Axl.

"It's the best thing ever," Duhamel, 40, told Access Hollywood of parenthood. "It's the best thing that's ever happened to me. It's fantastic."

It's so fantastic, in fact, that the star is worried Axl has given him and the Black Eyed Peas singer, 38, a false sense of comfort. "He's a really good little baby, which means the second one will be a holy terror!" the proud papa quipped, laughing. 

So a second one is in the cards? "Of course! Yeah, we've gotta move fast," the actor said, noting that he and Fergie are "beyond happy."

Married since 2009, the elated couple welcomed their first child together on Thursday, Aug. 29, in L.A. A few days after Axl's birth, Duhamel took to Twitter to thank fans for their well wishes.

"All is good!" he tweeted. "In fact, never better. Much love, JD."