5. Mary Lynn Rajskub as Mitchell's ex-girlfriend (Season 2, Episode 12, "Our Children, Ourselves") In a comedy of errors that could only happen on Modern Family, Mitchell (Jesse Tyler Ferguson) becomes convinced that he has fathered a son with his former girlfriend Tracy (Mary Lynn Rajskub). Turns out the short-of-stature redheaded guy Mitch spots her with at the mall is her husband, not their lovechild. The vertically challenged fella is less-than-appreciative of the "Little Slugger" baseball mitt Mitchell and Cameron (Eric Stonestreet) give him as a bonding gift. Mary Lynn's signature deadpan face is the perfect foil to Cam and Mitchell's over-the-top reactions.
4. Ed Norton as an '80s rock star (Season 1, Episode 8, "Great Expectations") In one of the funniest episodes of Modern Family, Edward Norton makes a guest appearance as the bassist of '80s band Spandau Ballet. Thinking it's Phil's (Ty Burrell) favorite band, Claire (Julie Bowen) invites Ed's rocker character to the Dunphy house to put on a private concert as an anniversary gift. But Spandau Ballet is so not Phil's favorite band — in fact, he doesn't even know any of their songs, which makes for an extremely awkward evening.
3. Fred Willard as Phil's goofball dad (Season 1, Episode 21, "Travels With Scout") This Christopher Guest favorite was born to play Phil's goofy dad, Frank. Arriving in an RV and hiding secret pain behind a defense mechanism of constant jokes (gee, wonder where Phil gets THAT), Grandpa Dunphy eventually reveals that he's sad about the dog, Scout, he brought to give the family. Phil gives the dog back to Frank, and he, the pup, and the RV ride off into the sunset.
2. Shelley Long as Mitchell and Claire's estranged mom (Season 1, Episode 4, “The Incident”) Cheers icon Shelley Long is perfect as Claire and Mitchell's firecracker mom, DeDe. Unseen by the family since "the incident" at Jay (Ed O’Neill) and Gloria's (Sofia Vergara) wedding, where she became obnoxiously drunk and belligerent, she comes to town looking for forgiveness. Still upset with Gloria (and vice versa), the episode caps with a hilarious catfight between the two Mrs. Pritchetts. In a later episode, she returns with Claire’s high school boyfriend (guest star Matt Dillon) in tow as her lover. We hope she comes back again soon... with Matt.
1. Nathan Lane as Cam and Mitchell's annoying friend Pepper (Season 2, Episode 3, “Earthquake”) Broadway and film legend Nathan Lane stars as Mitchell and Cam's friend Pepper Saltzman. Besides having the best character name ever, Nathan is flawless as the overbearing and flamboyant Pepper, whose themed brunch the guys ditch by using an earthquake as an excuse. Nathan reappears in a later episode and ends up bonding with Jay over a night of boozing.
Who are your picks for best guest appearances on Modern Family — and who do you hope will reappear in Season 3?