This Christmas Vacation t-shirt features an image of Clark W. Griswold wearing a Santa Claus hat. The shirt reads And We're Gonna Have The Hap Hap Happiest Christmas. When guests staying at the Griswold house for Christmas tried to leave, Clark stopped them and told them they were going to press on and have the hap, hap, happiest Christmas since Bing Crosby tap-danced with Danny Kaye. For any fan of the jolliest movie this side of the nuthouse, this Hap Hap Happiest Christmas Vacation t-shirt is a must have!