Uncle Frank, brother to Kevin's dad, is the same kind of amusing jerk as Buzz—just grown-up. Frank prevents Kevin from watching Angels with Filthy Souls, encourages his wife to steal crystal glassware on the airplane to France, and lets his brother pick up the tab on the pizza they've ordered without offering to chip in a cent.
When Kevin inadvertently causes a bottle of Pepsi to spill on Frank, Frank responds,
FRANK: Look what you did, you little jerk.
His insensitivity and hilarious idiocy are further in evidence when Kevin's mom gets extremely upset over the fact that they forgot Kevin. Here's how Frank comforts her:
FRANK: If it makes you feel any better, I forgot my reading glasses.