Celebrities just have better genes than the rest of us. It’s undeniable. Naomi Watts – already gorgeous and thus carrying some obviously great genes – has already lost the vast majority of her pregnancy weight, just a month after giving birth to son Samuel Kai Schreiber. Naomi looked absolutely glowing last night at the New York premiere of boyfriend Liev Schreiber’s film “Defiance.” Celebs just seem to be able to bounce back from pregnancy much quicker than the rest of us.

New moms, eat your hearts out. On Monday – only two days shy of a month after giving birth to her second child – Naomi Watts was close to having back her pre-baby figure, as evidenced at the Cinema Society and Nextbook.org-sponsored New York premiere of her partner Liev Schreiber’s World War II drama Defiance.

How did she manage to drop the baby weight so quickly? “I’m breast feeding,” Watts, 40, told PEOPLE about her routine with Samuel Kai Schreiber. “And he’s sucking it all out of me, it seems. And when the baby comes out, it’s a lot of weight right there.”

A couple since 2005, Watts, 40, and Schreiber, 41, also have another son, Alexander Pete Schreiber, born in July 2007.

“They’re very different,” Watts said of her two boys. “[Sammy]’s more fragile, in a way. But I don’t know, maybe I’ve forgotten how small they are. [Alexander] is only 18 months old.

“And I’ve also got this big baby right here,” she said, pointing to Schreiber at her side on the red carpet.

[From People]

Not everyone is as lucky as Naomi and able to lose baby weight by breastfeeding. In April Salma Hayek told Oprah that she didn’t lose weight due to it, and had to work hard at diet and nutrition.

A lot of people make is sound like all you have to do is breastfeed and the weight will just fall off. I remember some episode of “Desperate Housewives” where a character said it was like doing an hour of cardio. Not that anyone should ever rely on that show for health advice. It was a nice idea, but it definitely seems to be untrue for most women. Naomi must be one of the very lucky few if that’s what’s responsible for most of her weight loss. She’s probably eating well too, and no matter what she looks absolutely stunning.

Here’s Naomi and Live at the “Defiance” premiere, held at the Sunshine Theater in New York City last night. Images thanks to Fame.