Knox, 4, mirrored his father as he stepped out in a zippered pants, blazer and aviator-style shades, reported People magazine. The couple took Knox and his twin sister Vivienne to the Natural History Museum in Los Angeles, where the young duo were smitten with the dinosaur exhibits.

"The tiny tykes had a blast playing with fossils, putting together a Tyrannosaurus Rex puzzle and looking at specimens through a microscope while they were there," a source said.u00a0

Brad Pitt. Pic/Santa Banta