Cliff (John Ratzenberger) is none too thrilled when his mother (Frances Sternhagen) pays an extended visit. Making matters worse, Mom takes a shine to Woody (Woody Harrelson), virtually adopting the affable bartender as "the son I never had." Back at Cheers, the gang tangles with some construction workers, and Norm (George Wendt) gets stuck in a barred window. ~ Hal Erickson, Rovi