Rick and Morty fan theory suggests Tammy Gueterman is the granddaughter of Rick Sanchez from an alternate universe, and here's how it works. The hit Adult Swim animated series created by Dan Harmon and Justin Roiland has captured the imaginations of viewers for the last several years and created one of the most dedicated fan bases in the process. Rick and Morty follows the adventures of Rick and his grandson Morty Smith across the multiverse, with their extended family also routinely involved in their lives.

Other than Rick and Morty, there are three family members who usually are somewhat involved with the show's adventures or receive sub-plots of their own: Rick's daughter Beth, her husband Jerry, and their daughter Summer. Despite the unlimited possibilities of the multiverse, though, Rick's family usually contains the same four people. Rick's wife has barely been explored, but in the different universes of Rick and Morty, Beth and Jerry are together more often than not and have Morty and Summer as their only two kids. However, the existence of the multiverse means there must be some variances - and Tammy Gueterman might be one of them.

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On the surface, Tammy Gueterman is just one of Summer's close friends who became romantically involved with Birdperson. She was later revealed to be a deep undercover agent for the Galactic Federation, with her Earth parents revealed to by cyborgs as part of her cover. But some Rick and Morty viewers believe that there is even more to Tammy than she's shown. According to the theory, Tammy is Rick's granddaughter from a different universe. This theory popped up because Tammy looks similar to Beth, has Jerry's brown hair, and is a super-genius like her possible grandpa.

Tammy being Rick's granddaughter is a popular Rick and Morty theory, but there are a few different possible explanations for how this could be possible. The simplest solution would see alternate versions of Beth and Jerry have a daughter that looks different than Summer. Some more complicated versions of the theory suggest that Tammy could be the offspring of another one of Rick's daughters in the multiverse. In either case, Rick and Morty hasn't provided much evidence to back up this claim - unless fans want to read Tammy and Summer dueling with lightsabers in Never Ricking Morty as an homage to the many familial lightsaber fights Star Wars has featured.

If the theory is one day proven to be accurate, it will bring another layer to Tammy that Rick and Morty could explore later on. It would be fascinating to learn that Tammy has known about her relationship to Rick this entire time and that her role in the series has been connected to her trying to find the right time to unveil this news. But Rick and Morty could just as easily have Rick be the one to discover this bombshell and put the responsibility on him to decide whether or not to tell Tammy about her true lineage. Either way, Tammy being the granddaughter of Rick wouldn't be the most shocking twist Rick and Morty has ever pulled, so fans will have to keep tuning in to see what future seasons reveal.

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