Madonna’s 11-year-old son Rocco joins her on stage

Madonna's adorable son Rocco Ritchie joined his mom on stage to help her kick off her MDNA world tour in Tel Aviv, Israel, on Thursday. Check out his multiple costumes — including a priest's robe! Plus, Charlize Theron shows off her chic style in London, and we're taking a look at some of the best celeb Twitpics of the week. Let us know on Facebook or Twitter which are your favorites — and why!

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