In the subplot, Lisa organizes a massive slumber party at the Retirement Castle to fix her reputation as a "party pooper".
The party gets out of control, and Lisa realizes she can't manage the chaos.
This visual aid forces Grampa to finally understand Homer's resentment. He admits that he wasn't hard on Homer because Homer was a "bad kid," but because being a father made him feel old, whereas Calvin makes him feel young. Secondary Feature: The "Cool Narc" Slumber Party [S34E8] Step Brother from the Same Planet
Homer enters a taxidermy convention with a crude display—two shells with googly eyes—representing himself and his father.
By convincing Chief Wiggum to drive her off in the back of a police car, she creates the illusion that she is a rebel, preserving her new "cool" status while successfully shutting down the party. In the subplot, Lisa organizes a massive slumber
She "narks" on her own party by calling the police, but then uses a staged arrest as a social feature.
The most distinctive "feature" of the episode is the use of as a communication tool. He admits that he wasn't hard on Homer
Watch this breakdown for a closer look at the rivalry between Homer and his new step brother, Calvin: