Rick's Father (known only as Mr. Sanchez) was the father of Rick Sanchez, the father-in-law of Mrs. Sanchez/Diane Sanchez, the paternal grandfather of Beth Smith, and the maternal great-grandfather of Summer Smith and Morty Smith, his name is unknown and he has never been seen in the show. He was mentioned in the episode Auto Erotic Assimilation.
In the episode Auto Erotic Assimilation, Rick and Unity were going to have an extremely kinky sex orgy, which involved multiple different things. One of Rick's requests was so that "Every man that remotely resembles his father would watch."
- Although it is unknown what Mr. Sanchez looks like, after Rick's sex orgy with Unity, involving every man that looks like his father, there was a group of short, middle-aged men with short hair that were all wearing white, short sleeved shirts, blue ties, gray pants and glasses. This could be a hint toward what Rick's father's appearance and usual clothing attire is. He seems to have been a bureacrat, this could be an explanation to Rick's hatred towards bureaucrats.
- What we could possibly tell is that Rick's father wasn't a good supporter in Rick's childhood. That's probably one reason why he had him there in the first place.