Why don't I get Beth and we'll go out for ice cream?

*Diane Sanchez is the deceased wife of Rick Sanchez and the mother of Beth Sanchez.

Diane's death was the defining moment in Rick's life that made him into who he is. The story of Diane has been the overarching mystery of the series from Season 1 up until Season 5. She and Beth were murdered by another Rick via an explosion from a futuristic bomb. The trauma from her murder caused Rick to spiral into a vengeful rampage, sending him on a journey to avenge his dead wife and daughter by finding the Rick that killed her.

As revealed in "Unmortricken", After Diane C-137's death, Rick Prime used the Omega Device to kill one of her counterparts, effectively erasing Diane across infinity.

Diane Sanchez was a slim, fair-skinned woman with medium-length light blonde hair. She had plump cheeks, an upturned nose, prominent punch-pink lips, and several freckles on her heart-shaped face.

The only outfit she has been canonically shown wearing so far consists of a light turquoise blouse, white jeans, gray cone heels, a silver pendant necklace, a violet bangle on her right arm, and a gold wedding ring on her left ring finger.

In "Fear No Mort," however, a simulation of Diane inside the Fear Hole is shown wearing different outfits aside from her usual attire. This includes her in a light turquoise nightgown paired with a dark blue robe, and another outfit where she wears a turquoise halter dress, gray cone heels, and a pearl bracelet.

Diane's only presence in the show (thus far) has been through references, flashbacks, tech in her likeness, and simulations[1]. Despite only appearing as a supernatural simulation, "Fear No Mort" marks her first major appearance yet. Diane is voiced by Kari Wahlgren, the same actress who voices Jessica, the Space Cruiser and the Garage AI, among others. The fact that Rick had originally created an AI with Diane's voice in Dimension C-137 suggests some unknown link to the Space Cruiser and Garage AI. This was confirmed in "Unmortricken". In "Solaricks" and in "Wet Kuat Amortican Summer", Rick mentions that Summer reminds him of her grandmother. This implies that she and Diane have similar personality traits. Before Diane was confirmed to be the actual maternal grandmother of Summer and Morty, Giahna Pantano, an artist who did alternative covers for two issues of Oni Press' Rick and Morty comics, created a character named "Bonnie Sinclair" to fill the roles of Rick's wife and Beth's mother[6].*