Rob, 27, booked a flight from Florence to Los Angeles in a hurry and sources said he was in tears while trying to secure a seat.
Unlike the rest of his family, Rob had been keeping a low profile abroad. While his mother and sisters were seen hitting up all the tourist spots in the City of Light, Rob was never photographed, reported Us magazine.
He was also conspicuously absent from the group's feast at Hotel de Costes, and from the Friday morning brunch at Valentino's Chateau de Wideville.