Brad Pitt and Angelina Jolie take twins Vivienne and Knox on a trip to Paris

They only arrived in Venice last week, but it seems Brad Pitt and Angelina Jolie already have itchy feet.The couple and their six children were expected to stay in the Italian city for three months, but were spotted heading off to Paris yesterday.Pitt and Jolie each clasped one of their 19-month-old twins as they boarded a water taxi to the airport. Family trip: Angelina Jolie and Brad Pitt