Be careful, girls!

With Kourtney Kardashian holding on to baby Mason, she and sister Kendall Jenner ran across the busy Pacific Coast Highway in Malibu. The sisters were there to hang out at the beach with Mason's daddy Scott Disick.

We couldn't help but notice that Mason is wearing Shrek ears. Such a cutie! See a close-up of the little toddler's green attachments ... after the jump.