Ben Stiller knows a thing or two about overprotective fathers. He went up against one (Robert De Niro) in last year's hit comedy Meet the Parents, and in his new family satire The Royal Tenenbaums (opening Dec. 14), he plays an obsessively cautious doomsday dad who dresses his offspring in red sweatsuits and guides them through rigorous emergency drills.

Now that Stiller and his wife, actress Christine Taylor, are expecting their first child, the funnyman admits he can relate to his alter ego's parental paranoia — not that he'll be taking any cues from him. "He's pretty extreme," the Zoolander star tells TV Guide Online. "I don't foresee us getting matching sweatsuits for my kids or anything like that."

Stiller, the son of legendary comedians Jerry Stiller and Anne Meara, says his wife broke the baby news to him in a greeting card earlier this fall. "It had a little baby on it and it said, 'We're pregnant,'" he recalls with a grin. "It's an incredible realization, and it's exciting to think about who this person is going to be.

"There's a certain sense of not believing it's actually happening," he adds, "until you start to see that she's getting bigger, and going to the doctor to see the ultrasound, and things like that."

Although the baby's gender is still a mystery, the onetime Saturday Night Live regular confides that he's hankering for a son. Yet if Baby Stiller turns out to be a girl, might Dad wreak havoc on her future suitors &#224 la De Niro in Meet the Parents? "I have no idea what I'm going to be like with a girl," says the thesp, who's slated to star in the Meet the Parents sequel, Meet the Fockers (due in 2003). "I assume I'm going to be protective, because I already feel that way. But I don't want to be overprotective, either."