First lady Michelle Obama during her guest appearance on the Nickelodeon sitcom, “iCarly.” (Lisa Rose/Nickelodeon)

You may have seen previews of Michelle Obama on Nickelodeon’s “iCarly” where she says a few lines and busts a few dance moves. Monday’s broadcast will be the first time a first lady has appeared on a sitcom since Nancy Reagan did “Diff’rent Strokes” 29 years ago.

“Diff’rent Strokes” starwith Nancy Reagan at the White House. (The Washington Post Archives)

Reagan got flack for her “Just Say No” campaign — but millions of viewers with “Diff’rent Strokes.” The former actress did advance publicity with star Gary Coleman; on the “very special episode” in March 1983 she warned youngsters about the dangers of using drugs.

After that. . . not much. Hillary Clinton never appeared on a sitcom during her years as first lady, said Anthony — not even for close friend Linda Bloodworth-Thomason, whose “Designing Women” was on air during her first White House year. She did pop up on “Sesame Street” — as did Barbara Bush (the first first lady to co-star with Muppets), Laura Bush and Obama — to tout kid-friendly initiatives.

Betty Ford (center), producer Ed Weinberger (left), and Mary Tyler Moore rehearsing a scene at the Hay-Adams Hotel. (Joe Heiberger)

Obama said she agreed to appear on “iCarly” because Malia and Sasha are big fans of the show and its main character (played by actress Miranda Cosgrove) is the daughter of an Air Force Colonel deployed overseas. On the episode, the first lady thanks Carly and other military families for their service, then jumps into the show’s “Random Dancing” bit. Obama will also appear live with the cast and military kids Friday at Hayfield Secondary School in Alexandria to promote the broadcast and answer questions.

Read also: First lady Michelle Obama is guest on ‘iCarly’, 1/10/12

Teen star Miranda Cosgrove talks about first lady Michelle Obama’s appearance on 'iCarly’, 1/5/12