Uncle Grandpa's Uncle Grandpa is a series of Uncle Grandpas that bears resemblance and intelligence to one another as seen in the episode Uncle Grandpa's Uncle Grandpa. They are voiced by Pete Browngardt and Kevin Michael Richardson.
Uncle Grandpa's Uncle Grandpa looks like a bigger and fatter version of Uncle Grandpa, although he is a little more dimwitted and slower to Uncle Grandpa. His Uncle Grandpa is a very small version of Uncle Grandpa with slightly more intelligence as he brought more ideas into consideration. Mr. Gus' Uncle Grandpa is giant Godzilla Uncle Grandpa with his appearance and Uncle Grandpa's features, he also has the same level of intelligence as the first two Uncle Grandpas.
The Uncle Grandpas are to show up when Uncle Grandpa has a problem and when his Uncle Grandpa has a problem. They all appear to have the same level of intelligence as shown in the episode as they all kept suggesting they use a different condiment to solve their problem. Uncle Grandpa's Uncle Grandpa seems to bee the more dimwitted out of all of them as he took a while to respond to Uncle Grandpa while in Greece and was the one to start the chain of condiment use. His Uncle Grandpa turns out to be a little more inelegant as he offered more ideas even though they were all condiment related and Mr. Gus' Uncle Grandpa seems to be a little more like Mr. Gus although sharing in the stupidity of the other Uncle Grandpas.
- Although Uncle Grandpa is supposed to be everyone in the world's Uncle Grandpa, Mr. Gus has his own Uncle Grandpa although this was just another Uncle Grandpa made to look like him.