Brad Pitt, who's up to his elbows in poopie diapers, found an oh-so-fitting way to describe the number of tykes he and Angelina Jolie figure will eventually call them Mom and Dad.

"I think we'll crap out somewhere between seven and nine," the perma-capped do-gooder told Charlie Rose this week. (Like his hat? Contribute to his efforts to help New Orleans by buying one here.)

When Rose awkwardly giggled and asked, "Are you serious?" Pitt responded, "Yeah, somewhere in there, we'll crap out."

For now, he's chugging along in daddy mode, especially when it comes to picking out Christmas gifts for Maddox, 6, Pax, 4, Zahara, 2, and Shiloh, 1.

According to Regis Philbin (via Us), who taped an interview with Brad this week, he's planning to treat the tots to a trip down memory lane when the family rings in the holiday at their French Quarter mansion.

"He got quite nostalgic, buying them the presents that he got as a kid years ago," says Reege, who was lacking in specifics save for the presents will include "trains."

In the meantime, Pitt may still be picking glitter out of his hair from his Dec. 18 birthday (he turned 44). OK! says his three older kids decided to construct personalized cards for his big day.

Brad Pitt and Zahara Jolie-Pitt at Central Park in New York on Aug. 28

"Zahara loves coloring and said she wanted to make a card for Daddy," a mole tells the mag. "[She] went a little crazy with the glitter, and it ended up all over the house!"

Angelina, who last year surprised Brad with a tour of Frank Lloyd Wright's famed Fallingwater house in Pennsylvania, supposedly opted for something a little less enriching this time out.

OK! claims she presented Pitt with a new motorcycle to add to his ever-growing collection.

Either way, adds a sentimental mole, "His family is the best birthday gift Brad could ever have."

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