The Big Bang Theory Wiki

Edward "Stumpy" Tucker is Sheldon's maternal uncle and Mary Cooper's brother. He is mentioned in "The Zazzy Substitution".

Mary says that if she hadn't told her brother Stumpy not to clean the wood chipper by hand they'd still be calling him "Edward".

He is also mentioned in the "Young Sheldon" prequel series. However, this is by Meemaw who doesn't mention Edward precisely, rather saying to Mary that she is the only child she has still talking to her, meaning Edward and their brother Carl are estranged from Meemaw.