The actor died after a long battle with MS.
David Lander, known as Squiggy on Laverne & Shirley, has died. He was 73.
The actor died of multiple sclerosis on Friday evening at Cedars-Sinai Medical Center in Los Angeles, according to multiple reports. ET has reached out to Lander's rep for comment.
In an exclusive statement to ET, actor Michael McKean -- who played Lenny Kosnowski on Laverne & Shirley -- remembered Lander for his sense of humor.
"David was my friend for fifty-five years," McKean tells ET. "He was the funniest man I ever knew, and faced a hideous illness with guts and humor. Ask anyone who knew him, you'll get the same story. Possibly a genius, definitely a great friend."
Lander battled MS for 37 years. He went public with his diagnosis in 1999 and was a Goodwill Ambassador for the National Multiple Sclerosis Society. He wrote about his MS in his 2002 autobiography, Fall Down Laughing: How Squiggy Caught Multiple Sclerosis and Didn't Tell Nobody.
The New York native had dreams of becoming an actor since the age of 10, studying at the High School for the Performing Arts, Carnegie Tech and New York University.
While at Carnegie, Lander and Michael McKean developed the character of Lenny and Squiggy, which would go on to be featured in the 1976 sitcom Laverne & Shirley. The show went on for eight seasons before it wrapped in 1983.
Lander and McKean would go on to work together in Steven Spielberg 1979 comedy 1941, Used Cars (1980), and voice characters on the animated series Oswald.
The late actor also appeared in shows like The Bob Newhart Show, Barney Miller, Happy Days, Viva Valdez, Married... with Children, Twin Peaks, Mad About You, Pacific Blue and The Drew Carey Show. His films include A League of Their Own, Say It Isn't So, Christmas With the Kranks, A Bug's Life, Who Framed Roger Rabbit and many more.
Upon hearing the news of his death, dear friend McKean posted a touching photo of the two.
Dane Cook also tweeted: "RIP David Lander aka 'Squiggy' on Laverne & Shirley. I hope when you were reunited with the great Penny Marshall you greeted her with a hug and a 'Hellooo Lavernnne!'"
Henry Winkler also expressed his condolences on social media.
Lander is survived by his wife, Kathy Fields, and daughter Natalie Lander.