1. Marshall and Williams first worked together as writers for Francis Ford Coppola

Around the time of our nation's bicentennial, Godfather director Coppola was producing a spoof dubbed "My Country Tis of Thee." Marshall and Williams were on the writing team, along with Steve Martin, Martin Mull and Harry Shearer. Garry Marshall, Penny's brother, would pluck the two and cast them as Laverne and Shirley. The characters made their debut in a third-season episode of Happy Days titled "A Date with Fonzie" in 1975.

Image: The Everett Collection

2. Spinal Tap appeared together in one episode.

Speaking of Harry Shearer, the writer/actor guest-starred in the season-three Laverne & Shirley episode "Bus Stop." Also appearing in that episode was Shearer's longtime collaborator Christopher Guest. Of course, Guest, Shearer and Michael McKean, a.k.a. "Lenny," would soon go on to make the cult classic mockumentary This Is Spinal Tap — which was directed by Penny Marshall's ex-husband, Rob Reiner. Lenny does not appear much in the eighth season, as McKean was busy filming Spinal Tap.

3. Lenny and Squiggy were created long before the show.

Michael McKean and David Lander were friends going back to college in Pittsburgh. As students at Carnegie Mellon University, the two were part of a comedy troupe named the Credibility Gap and created the characters Lenny and Squiggy (original name: Anthony Squiggliano) for skits. McKean and Lander were brought on as writers for Laverne & Shirley, after which their old alter-egos were revived and injected into the sitcom.

Image: The Everett Collection

4. The show recycled scripts from a 1966 Garry Marshall flop.

The forgotten 1966 sitcom Hey, Landlord! had two things going for it. Quincy Jones wrote the theme music, for starters. Secondly, its creator was TV icon Garry Marshall. However, the show was a bust. The material couldn't have been so bad, though, as some scripts were reused for Laverne & Shirley. For example, Landlord's "Testing…One, Two" was turned into "Guinea Pigs," right down to using the same character, Dr. Sandor.

Image: jacksonupperco.com

5. The apartment set was recycled, too.

Though it was obviously completely redecorated, the guts of The Odd Couple condo was used to craft Laverne and Shirley's garden apartment. You can spot the similarities in the entryways to the right, seen here, which feature two doors at a right angle on a raised platform.

6. Most of the Marshall family was involved in the making of Laverne & Shirley.

Obviously, Penny Marshall starred — and she directed some episodes, too. Her brother Garry created, produced, directed and scripted. Ronny Hallin, their sister, served as the show's casting director. Oh, and Anthony Marshall, their father, produced as well.

Image: AP Photo / Nick Ut

7. Laverne and Shirley joined the Army for a Hanna-Barbera cartoon.

Marshall and Williams actually voiced their animated incarnations for Laverne & Shirley in the Army, which appeared on Saturday mornings in the fall of 1981. As it was a cartoon, the plots got quite surreal — the two military newbies faced off against aliens, werewolves and Bigfoot. Commanding over them was Sgt. Squealy, a talking pig, who was voiced by Ron Palillo — a.k.a. Horshack of Welcome Back, Kotter.

Image: Hanna Barbera

8. Pepsi Milk was an actual favorite of Penny Marshall's.

Pepsi Milk, which is just what it sounds like, was Laverne's comfort drink of choice on the show. The treat was an old favorite of Marshall's. She got in the habit of drinking it as a child, when her mother would make her drink a glass of milk before having some soda. Young Penny would top off her unfinished milk with a splash of cola and — voila! — a new treat. Here's a recipe if your tastebuds are curious. Or, you could head to Japan, where Pepsi made a strawberry milk flavor.

9. "Schlemiel! Schlimazel!" also comes from Marshall's childhood.

As Cindy Williams herself explained to us in an interview, the duo's hopscotch mantra was from Marshall's youth. "[Garry's] the one who told Penny, 'Teach Cindy that little ditty you used to do on the way to school. We'll shoot that.'" Williams said. "Penny taught me 'Schlemiel! Schlimazel!' I had no idea what it meant and I'm still kind of shakey on it…. When Penny and her school chums would walk to school, they'd link arms and count off their steps, '1, 2, 3, 4, 5, 6, 7, 8, schlemiel, schlimazel, hasenpfeffer incorporated!' Then they'd run and stop and start counting again. Garry remembered that."

10. It was mostly just 'Laverne' in the final season.

After years on the air, sitcoms tend to shake up the formula. In the fall of 1980, the entire Laverne & Shirley gang moved west, from Milwaukee to Burbank, California. Laverne and Shirley went from bottle-cappers to aspiring actresses and department store employees. Two years later, early in the eighth and final season, Cindy Williams became pregnant and left the show. Originally, there were plans to have her character Shirley pop in here and there, but that did not come to fruition. Instead, her parts were rewritten for guest stars, most notably in "The Baby Show," where Vicki Lawrence played an expecting mother.

11. The theme song by Cyndi Grecco hit the Billboard charts.

In July of 1976, "Making Our Dreams Come True" climbed to No. 25 on the charts. The tune would make singer Cyndi Grecco a one-hit wonder. The single was co-produced by Jose Feliciano's wife, Janna Merlyn Feliciano, and released on the Private Stock label, which was known for celebrity crooners. (Private Stock put out the debut full-length of Blondie, too.) The imprint also released singles by Vicki Lawrence, including "The Other Woman" — perhaps foreshadowing her fill-in role mentioned above?

Image: lyrics.wikia.com

12. Cyndi Grecco was discovered at Six Flags.

As Grecco herself explained to Dick Clark in a 1976 interview on American Bandstand, the singer had a gig at Six Flags Magic Mountain in California. She was performing there by the roller coasters when Charles Fox and Norman Gimbel, the ace songwriters, discovered her. The duo, who had previously written "Killing Me Softly with His Song" and "Happy Days," quickly asked her to sing "Making Our Dreams Come True."

Image: Dick Clark Productions

13. Both Laverne & Shirley and Lenny & Squiggy released albums.

Williams and Marshall recorded a rock & roll album as Laverne & Shirley. That LP is a story unto itself, with its ties to the Beach Boys, Phil Spector and Kenny Loggins. Lenny & Squiggy Present Lenny and the Squigtones was more of a success. The Squigtones even performed on an episode of American Bandstand.

Image: Atlantic Records / Discogs

14. Fred Dryer made his acting debut on the sitcom.

NFL defensive star Fred Dryer — the first man to record two safeties in one game in 1977 — decided to give acting a go late in his career. In 1980, as he was still played for the Los Angeles Rams (he would retire in 1981), the defensive end appeared in the sixth-season premiere of Laverne & Shirley, "Not Quite New York," the one where they move to California. Dryer appears as a lifeguard in Laverne's dream sequence. He would later be considered for the lead role on Cheers — which eventually went to Ted Danson, of course — but he ended up going the action route as the star of Hunter.

Image: ABC

15. Laverne and Shirley reunited on Ariana Grande's Nickelodeon show.

Sam & Cat was a spin-off of the popular teen sitcom iCarly. In a 2013 episode, Marshall and Williams appeared together as the feuding co-creators of a 1970s children's show called Salmon Cat. As you can see in this boxing scene, the two proved they still had those physical-comedy chops.

Image: Nickelodeon

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