It's revealed that Clayton's father had divorced Julia's mother and after he was born, divorced his mother and remarried Julia's mother and they had Suzanne. He always felt left out because "I like to think I was the product of my father's affair."
Clayton is played by legendary Georgia newspaper columnist/author, Lewis Grizzard. Much like the character, Clayton, Grizzard performed stand-up comedy as well.
This is the first time Clayton has been mentioned on the show and is the only episode that Clayton appears during the run of the show.
There was never any mention of any other Sugarbaker children or step parents by any character. According to Clayton, Mr. Sugarbaker, the family patriarch married Pesky and had Julia, he then divorced Pesky because he had a dalliance with his mother Dee Dee, a Rockette and had him. He stayed married to Dee Dee long enough to make Clayton's birth legitimate and then left her and remarried Pesky and had Suzanne. It is presumed that Julia, Pesky and Suzanne always knew about their brother and spent time with him due to them admitting that he was "an odd child who spent a lot of time in the basement." Julia and Suzanne are 12 years apart in age and Clayton is right in the middle, meaning Julia was 6 when he was born and he was 6 when Suzanne was born. Despite all this, they clearly love and appreciate each other. Clayton is never seen on the show again.
When the series began in 1986, Julia was 40 and Suzanne, her sister was 29 (her birthday was shown later, making her 30), the sisters are 12 years apart. As Clayton is 6 years younger than Julia and 6 years older than Suzanne, here, in 1988, Clayton would have been either about 35 years old, Julia would have been about 42 and Suzanne would have been about 32. Up to this point there was no mention or celebration for any birthdays for Julia, and only one for Suzanne, the aforementioned 30th in 1986.