McHale says his son met Glover when he was five when the stars were on the show together.
"My son Eddie would come to set and Eddie doesn't like to say, at that point he didn't want to say hi to anyone and I would kind of force him," McHale said of how his son was shy.
"I was like say hi to Donald and in his rebellion he'd always go 'hi stupid!' and it would always crack up Donald," McHale continued.
He said his son recently used the same nickname when he ran into the Star Wars star out in public, much to McHale's disappointment.
"He's 13 now, he's like the same size and he's got long hair. It looked like this little homeless man screaming at him," McHale joked about the encounter.
McHale and Glover starred together on Community for five seasons on NBC. The comedian recently had his Netflix series The Joel McHale Show with Joel McHale canceled after one season.