Justin Timberlake and Jessica Biel are going strong - but kids may not be in their future.

When asked if he'd like to have children at the Keep a Child Alive ball in NYC Thursday, Timberlake said: "I'm not sure."

What would Justin's kids look like? See his baby photo!

Timberlake has been an advocate for kids' charities. In addition to last night's event, he hosted a golf tournament to benefit the Shriners Hospitals for Children last month.

So have American Idol producers asked him to perform on their annual Idol Gives Back special?

"I haven't been invited," he said.

But, he's not a fan of the show anyway: "I don't watch a lot of television," he admitted.

Check out stars doing good deeds for Idol Gives Back.

Instead, the singer is focusing on his move to NYC. He and Biel (who moved into his six-bedroom L.A. home this summer) are close to closing on an apartment in the Pearline Soap Factory building in the exclusive Tribeca neighborhood. A source tells Us they may even combine two floors!

"It's the greatest city in the world!" he told reporters of his choice to relocate to the Big Apple.

"It's good for everything," he added. "It's good for food, there's some good fashion, there's mostly good weather except for today and it's the realest city in America." >>>>