1x14 - Maniac Mansion

The family is worried whether Uncle Lenny will make it to the mansion for Christmas because of a big storm that's predicted. Kiefer tells Turner that Santa Claus doesn't exist. Meanwhile Lenny's dogsled gets snowed in, he hitches a ride on a plane, falls off it and collapses in the snow. Turner goes to sleep asking Santa to forget about all the presents for him and to help his Uncle instead. Santa comes to Turner (in a dream?) and takes him to where Lenny is lying in the snow and they bring him home for Christmas.