Celebrity Social Media Pictures | Week of Oct. 18, 2012

It was all blue skies, beach trips, and birthdays for some of our favorite celebs on social media this week. Bar Refaeli got into a pretty intense water fight with a pint-size pal on the beach, while Miley Cyrus got in the Halloween spirit with her little sister, Noah. Alessandra Ambrosio wore a bikini while hanging out with her daughter, Anja, by the ocean, and Stacy Keibler celebrated her birthday with pals Dave and Odette Annable.

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