The episode features guest star Melissa McCarthy as Calvin and received mixed reviews.
While retrieving Grampa's things at the retirement home, Bart and Lisa learn that his rent is still covered.
Meanwhile, Homer is allergic to the wax Marge used to polish the house surfaces, so he is forced to room with Calvin where they constantly fight.
On the way out, Lisa sits in the police car and convinces Chief Wiggum to pretend to arrest her to make her look cool.
At San Diego Comic-Con 2022, Matt Selman announced that Melissa McCarthy would guest voice as a rival for Grampa Simpson's affection.
[6] The song "Yours Is an Empty Hope" by the band Nightwish plays in the scene where Homer and Calvin prank each other.
[7] "Step Brother from the Same Planet" earned a 0.3 rating and 1.21 million viewers in its initial airing, which was the most watched show on Fox that night.