Nothing makes me laugh harder than any number of instances and one-liners from this, the very best of the “Vacation” series. Cousin Eddie’s lewd antics, Uncle Lewis’s cigar flame-out, Aunt Bethany’s quip about “Grace,” the haughty-taughty Chesters next door, a dazzling Christmas lighting display, a sight gag minutes removed from the snow sled race sequence it references, and indeed, “Merry Christmas, Merry Christmas, kiss my ass, kiss his ass, kiss your ass, Happy Hanukkah.” I spit out my eggnog every time. Just do yourself one massive favor: avoid the sequel at all costs.