Summer Smith

Summer is Morty's older sister, a high schooler navigating the ordinary hell of popularity and boys until she stumbles into her grandfather's garage full of interdimensional gadgets. She's sharp-tongued and image-conscious, initially dismissive of Rick and Morty's adventures, but curious enough to invite herself along once she realizes what's actually out there.

The show could have kept her as a sitcom-standard teenage afterthought, but it lets her insist her way into the sci-fi plot and rewards that insistence. Grammer plays her withering deadpan without ever losing the specific ache of a kid trying to look unbothered while everything around her is insane.