Penny Marshall (left) and Cindy Williams
06/27/2013 at 08:00 AM EDT
They're getting back together – for the kids.
and Cindy Williams
, who teamed up as Laverne and Shirley on the classic, eponymous sitcom from 1976 to 1983, are reuniting for a guest appearance on a teen sitcom. It will be the first time they've acted together in 30 years.
Marshall, 69, and Williams, 65, will appear on Nickelodeon's Sam & Cat
, playing the creators of a '70s TV show who haven't spoken in 30 years.
The episode is filming this week in Los Angeles.
Marshall has largely been out of show business in recent years. Last September, she published a memoir
, My Mother Was Nuts
, in which she discussed, among other things, her 2009 diagnosis of both a brain tumor and lung cancer – from which she recovered fully.
Williams has done TV, film and stage acting
, and some film producing, since Laverne & Shirley
Sam & Cat
, starring Jennette McCurdy and Ariana Grande, is a crossover spin-off of two other Nickelodeon shows – iCarly