03/03/2008 at 01:00 AM EST
The powder was fresh, the sky was blue, and Brad Pitt
and his two boys—Maddox, 6, and Pax, 4—were pumped to hit the slopes at California's Mammoth Mountain ski resort on Feb. 6. While the boys navigated their snowboards down a nearby bunny hill, their proud dad "was smiling at them," says Lacey Smith, who was there vacationing with her family. "Maddox was a natural, but it wasn't coming that easily for Pax. One of the times he fell down, Brad said, 'That's okay—way to go. Good job!'" Around noon, Pitt—who handled boy duty solo while daughters Zahara, 3, and Shiloh, 21 months, stayed warm inside—treated the brothers and their ski instructors to lunch before the entire group returned to the slopes. This time Pitt crouched behind his sons, catching them when they began to fall or herding them in the right direction when they veered off course. "He looked so happy to be up there with them," says Smith. "It was clear he was having as much fun as they were."
Family bonding is clearly the main agenda these days for Pitt, 44, and Angelina Jolie
, 32, who made the most of their wintry getaway to the town of Mammoth Lakes, a picturesque ski haven in the Sierra Nevada mountain range located about 300 miles from Los Angeles. Whether cozying up in their rented slopeside cabin, lunching at the lodge's cafeteria or cheering on their boys at Sledz tubing park, the couple kept things low-key and kid-centric—even as Jolie's puffy parkas and lack of ski time continued to fuel speculation that the actress may be expecting again. On the slopes Feb. 15, "she was just happy sitting back and watching," says an observer. Coming off of a two-day humanitarian mission to Iraq, the actress was obviously relishing the downtime. "I love being a mom," she said on a rare night out with Pitt at the Santa Barbara, Calif., film festival on Feb. 2, "and I think that's my big passion: my family." Baby on the way or not, for now, it's clear that she and Pitt are enjoying making memories with their tight-knit crew of six.